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1.
Hum Reprod ; 39(5): 1098-1104, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38498835

RESUMEN

STUDY QUESTION: Is there any difference in ovarian response and embryo ploidy following progesterone-primed ovarian stimulation (PPOS) using micronized progesterone or GnRH antagonist protocol? SUMMARY ANSWER: Pituitary downregulation with micronized progesterone as PPOS results in higher number of oocytes retrieved and a comparable number of euploid blastocysts to a GnRH antagonist protocol. WHAT IS KNOWN ALREADY: Although the GnRH antagonist is considered by most the gold standard protocol for controlling the LH surge during ovarian stimulation (OS) for IVF/ICSI, PPOS protocols are being increasingly used in freeze-all protocols. Still, despite the promising results of PPOS protocols, an early randomized trial reported potentially lower live births in recipients of oocytes resulting following downregulation with medroxyprogesterone acetate as compared with a GnRH antagonist protocol. The scope of the current prospective study was to investigate whether PPOS with micronized progesterone results in an equivalent yield of euploid blastocysts to a GnRH antagonist protocol. STUDY DESIGN, SIZE, DURATION: In this prospective study, performed between September 2019 to January 2022, 44 women underwent two consecutive OS protocols within a period of 6 months in a GnRH antagonist protocol or in a PPOS protocol with oral micronized progesterone. PARTICIPANTS/MATERIALS, SETTING, METHODS: Overall, 44 women underwent two OS cycles with an identical fixed dose of rFSH (225 or 300 IU) in both cycles. Downregulation in the first cycles was performed with the use of a flexible GnRH antagonist protocol (0.25 mg per day as soon as one follicle of 14 mm) and consecutively, after a washout period of 1 month, control of LH surge was performed with 200 mg of oral micronized progesterone from stimulation Day 1. After the completion of both cycles, all generated blastocysts underwent genetic analysis for aneuploidy screening (preimplantation genetic testing for aneuplody, PGT-A). MAIN RESULTS AND THE ROLE OF CHANCE: Comparisons between protocols did not reveal differences between the duration of OS. The hormonal profile on the day of trigger revealed statistically significant differences between protocols in all the tested hormones except for FSH: with significantly higher serum E2 levels, more elevated LH levels and higher progesterone levels in PPOS cycles as compared with antagonist cycles, respectively. Compared with the GnRH antagonist protocol, the PPOS protocol resulted in a significantly higher number of oocytes (12.7 ± 8.09 versus 10.3 ± 5.84; difference between means [DBM] -2.4 [95% CI -4.1 to -0.73]), metaphase II (9.1 ± 6.12 versus 7.3 ± 4.15; DBM -1.8 [95% CI -3.1 to -0.43]), and 2 pronuclei (7.1 ± 4.99 versus 5.7 ± 3.35; DBM -1.5 [95% CI -2.6.1 to -0.32]), respectively. Nevertheless, no differences were observed regarding the mean number of blastocysts between the PPOS and GnRH antagonist protocols (2.9 ± 2.11 versus 2.8 ± 2.12; DBM -0.07 [95% CI -0.67 to 0.53]) and the mean number of biopsied blastocysts (2.9 ± 2.16 versus 2.9 ± 2.15; DBM -0.07 [95% CI -0.70 to 0.56]), respectively. Concerning the euploidy rates per biopsied embryo, a 29% [95% CI 21.8-38.1%] and a 35% [95% CI 26.6-43.9%] were noticed in the PPOS and antagonist groups, respectively. Finally, no difference was observed for the primary outcome, with a mean number of euploid embryos of 0.86 ± 0.90 versus 1.00 ± 1.12 for the comparison of PPOS versus GnRh antagonist. LIMITATIONS, REASONS FOR CAUTION: The study was powered to detect differences in the mean number of euploid embryos and not in terms of pregnancy outcomes. Additionally, per protocol, there was no randomization, the first cycle was always a GnRH antagonist cycle and the second a PPOS with 1 month of washout period in between. WIDER IMPLICATIONS OF THE FINDINGS: In case of a freeze-all protocol, clinicians may safely consider oral micronized progesterone to control the LH surge and patients could benefit from the advantages of a medication of oral administration, with a potentially higher number of oocytes retrieved at a lower cost, without any compromise in embryo ploidy rates. STUDY FUNDING/COMPETING INTEREST(S): This research was supported by an unrestricted grant from Theramex. N.P.P. has received Research grants from Merck Serono, Organon, Ferring Pharmaceutical, Roche, Theramex, IBSA, Gedeon Richter, and Besins Healthcare; honoraria for lectures from: Merck Serono, Organon, Ferring Pharmaceuticals, Besins International, Roche Diagnostics, IBSA, Theramex, and Gedeon Richter; consulting fees from Merck Serono, Organon, Besins Healthcare, and IBSA. M.d.M.V., F.M., and I.R. declared no conflicts of interest. TRIAL REGISTRATION NUMBER: The study was registered at Clinical Trials Gov. (NCT04108039).


Asunto(s)
Hormona Liberadora de Gonadotropina , Inducción de la Ovulación , Ploidias , Progesterona , Femenino , Humanos , Inducción de la Ovulación/métodos , Progesterona/administración & dosificación , Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Adulto , Estudios Prospectivos , Embarazo , Antagonistas de Hormonas/administración & dosificación , Antagonistas de Hormonas/farmacología , Blastocisto/efectos de los fármacos , Índice de Embarazo , Recuperación del Oocito , Transferencia de Embrión/métodos , Administración Oral , Inyecciones de Esperma Intracitoplasmáticas/métodos
2.
Medicine (Baltimore) ; 100(42): e27523, 2021 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-34678886

RESUMEN

BACKGROUND: Uterine fibroids are benign. They belong to the category of "abdominal mass" in traditional Chinese medicine, and pathogenesis is mainly caused by weakness of the body, qi stagnation, and blood stasis. Drug therapy is the preferred treatment of uterine fibroids in clinical practice, and mifepristone is the most commonly used drug. In the past decade, a large number of clinical randomized controlled trials have proven that Chinese patent medicine combined with mifepristone in the treatment of uterine fibroids has a better curative effect, fewer adverse reactions, and higher safety than mifepristone alone. However, there is a lack of evidence-based research. This study aims to integrate clinical data through network meta-analysis to provide more evidence-based medical evidence for clinical medication. METHODS: The comprehensive search included Chinese and other-language databases, such as MEDLINE (PubMed), Web of Science, The Cochrane Library, China National Knowledge Infrastructure, Wanfang Data Knowledge Service Platform, China Scientific Journal Database, and China Biomedical Literature Database. Clinical randomized controlled trials of 6 Chinese patent medicines combined with mifepristone for the treatment of uterine fibroids, including Guizhi Fuling Capsule, Gongliuxiao Capsule, Gongliuqing Capsule, Danbie Capsule, Gongliuning Capsule, and Xiaojiean Capsule were retrieved. The search period was from January 2010 to April 2021. Two researchers screened the literature through EndNote and used Excel to extract data. RevMan 5.3 was used to evaluate the quality of the literature. Treatment measures were analyzed in R language, and a forest map and probability ranking map of various interventions were drawn. The network evidence map and correction comparison funnel map of various interventions were drawn by STATA 14.0 software. RESULTS: This study provides the clinical efficacy and safety of network meta-analysis of 6 kinds of Chinese patent medicines combined with mifepristone in the treatment of uterine fibroids will be systematically evaluated or descriptively analyzed. CONCLUSION: This study's purpose is to provide a reference for the clinical treatment of uterine fibroids to choose more effective intervention therapies.


Asunto(s)
Antagonistas de Hormonas/uso terapéutico , Leiomioma/tratamiento farmacológico , Medicina Tradicional China/métodos , Mifepristona/uso terapéutico , Quimioterapia Combinada , Antagonistas de Hormonas/administración & dosificación , Antagonistas de Hormonas/efectos adversos , Humanos , Leiomioma/patología , Medicina Tradicional China/efectos adversos , Mifepristona/administración & dosificación , Mifepristona/efectos adversos , Metaanálisis en Red , Ensayos Clínicos Controlados Aleatorios como Asunto , Proyectos de Investigación , Metaanálisis como Asunto
3.
Fish Physiol Biochem ; 46(4): 1219-1227, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32146552

RESUMEN

Vertebrate ancient long (VAL)-opsin is a green-sensitive photoreceptor that shows high sequence similarity to vertebrate ancient opsin, which is considered to play a role in sexual maturation via gonadotropin-releasing hormone (GnRH); however, the role of VAL-opsin in vertebrate sexual maturity remains unclear. Therefore, we investigated the possible role of VAL-opsin in reproduction in the goldfish Carassius auratus under a state of GnRH inhibition. Goldfish were injected with recombinant VAL-opsin protein (0.5 µg/g body mass) and/or the GnRH antagonist cetrorelix (0.5 µg/fish), and changes in the mRNA expression levels of genes associated with goldfish reproduction were measured by quantitative polymerase chain reaction, including those involved in the hypothalamus-pituitary-gonad (HPG) axis, VAL-opsin, GnRH, the gonadotropins (GTHs) luteinizing hormone and follicle-stimulating hormone, and estrogen receptor (ER). Moreover, the fish were irradiated with a green light-emitting diode (520 nm) to observe the synergistic effect on the HPG axis with VAL-opsin. Green LED exposure significantly and slightly increased the VAL-opsin and GnRH levels, respectively; however, these effects were blocked in groups injected with cetrorelix at all time points. Cetrorelix significantly decreased the mRNA levels of GTHs and ER, whereas these hormones recovered by co-treatment with VAL-opsin. These results indicate that green LED is an effective light source to promote the expression of sex hormones in fish. Moreover, VAL-opsin not only affects activity of the HPG axis but also appears to act on the pituitary gland directly to stimulate a new sexual maturation pathway that promotes the secretion of GTHs independent of GnRH.


Asunto(s)
Opsinas de los Conos/fisiología , Carpa Dorada/fisiología , Hormona Liberadora de Gonadotropina/fisiología , Redes y Vías Metabólicas/fisiología , Reproducción/fisiología , Animales , Encéfalo/metabolismo , Femenino , Hormona Liberadora de Gonadotropina/administración & dosificación , Hormona Liberadora de Gonadotropina/análogos & derivados , Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Gónadas/fisiología , Antagonistas de Hormonas/administración & dosificación , Hipotálamo/fisiología , Fotoperiodo , Hipófisis/fisiología , ARN Mensajero/metabolismo , Distribución Aleatoria , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores de Estrógenos/genética , Receptores de Estrógenos/metabolismo , Proteínas Recombinantes
4.
Curr Pharm Biotechnol ; 16(2): 187-93, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25391244

RESUMEN

In this study, sustained-release of GnRH antagonist peptide LXT-101 was realized through oil formulation, and their releasing characteristics in vitro and in vivo were investigated. In this formulation, the static interaction between cationic charged peptide LXT-101 and the negative charged phospholipid led to the formation of the phospholipid-peptide complex, by which LXT-101 was completely dissolved in oils. This formulation was prepared by mixing an aqueous solution of LXT-101 and empty SUV (small unilamellar liposomes) containing EPC (phosphatidylcholine) and DPPG (1, 2-dipalmitog-sn-glycero-3- phosphoglycerol) at an appropriate ratio, the mixture was subsequently lyophilized, and the resultant was dissolved in the oil to form a clear oily solution containing solubilized peptide LXT-101. With atomic force microscopy combined with Langmuir-Blodgett technology, the morphology of the particles in the oily solution were examined to be oval-shaped and the mean particle size was 150 nm in diameter. In pure water at 37°C, about 70~90 % of LXT-101 was released slowly from the oily formulation over 7 days. An effective sustained suppression of testosterone in beagle dogs could be achieved over a period of seven days with this LXT-101 oily formulation, by i.m. at a dose of 0.2 mg/kg (2 mg/ml). This formulation dramatically improved the bioactivity of LXT-101 compared to its aqueous solution. It was also found that when the concentration of peptide LXT-101 was up to or over 10 mg/ml in aqueous solution, there was no significant difference between the oily formulation and aqueous solution. This fact meant that LXT-101 itself could conduct sustained release in vivo by self-assembly of nanofibers.


Asunto(s)
Antagonistas de Hormonas/administración & dosificación , Oligopéptidos/administración & dosificación , Animales , Preparaciones de Acción Retardada/administración & dosificación , Preparaciones de Acción Retardada/química , Preparaciones de Acción Retardada/farmacocinética , Perros , Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Antagonistas de Hormonas/sangre , Antagonistas de Hormonas/química , Antagonistas de Hormonas/farmacocinética , Inyecciones , Liposomas , Masculino , Ácido Oléico/química , Oligopéptidos/sangre , Oligopéptidos/química , Oligopéptidos/farmacocinética , Fosfatidilcolinas/química , Fosfatidilgliceroles/química , Aceite de Soja/química , Testosterona/sangre , Triglicéridos/química , Agua/química
5.
Am J Physiol Regul Integr Comp Physiol ; 305(4): R404-13, 2013 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-23785073

RESUMEN

Acupuncture or electroacupuncture (EA) potentially offers a nonpharmacological approach to reduce high blood pressure (BP). However, ~70% of the patients and animal subjects respond to EA, while 30% do not. EA acts, in part, through an opioid mechanism in the rostral ventrolateral medulla (rVLM) to inhibit sympathoexcitatory reflexes induced by gastric distention. CCK-8 opposes the action of opioids during analgesia. Therefore, we hypothesized that CCK-8 in the rVLM antagonizes EA modulation of sympathoexcitatory cardiovascular reflex responses. Male rats anesthetized with ketamine and α-chloralose subjected to repeated gastric distension every 10 min were examined for their responsiveness to EA (2 Hz, 0.5 ms, 1-4 mA) at P5-P6 acupoints overlying median nerve. Repeated gastric distension every 10 min evoked consistent sympathoexcitatory responses. EA at P5-P6 modulated gastric distension-induced responses. Microinjection of CCK-8 in the rVLM reversed the EA effect in seven responders. The CCK1 receptor antagonist devazepide microinjected into the rVLM converted six nonresponders to responders by lowering the reflex response from 21 ± 2.2 to 10 ± 2.9 mmHg (first vs. second application of EA). The EA modulatory action in rats converted to responders with devazepide was reversed with rVLM microinjection of naloxone (n = 6). Microinjection of devazepide in the absence of a second application of EA did not influence the primary pressor reflexes of nonresponders. These data suggest that CCK-8 antagonizes EA modulation of sympathoexcitatory cardiovascular responses through an opioid mechanism and that inhibition of CCK-8 can convert animals that initially are unresponsive to EA to become responsive.


Asunto(s)
Presión Sanguínea , Electroacupuntura , Hipertensión/prevención & control , Mecanotransducción Celular , Bulbo Raquídeo/metabolismo , Reflejo , Sincalida/metabolismo , Estómago/inervación , Animales , Presión Sanguínea/efectos de los fármacos , Devazepida/administración & dosificación , Modelos Animales de Enfermedad , Encefalinas/metabolismo , Antagonistas de Hormonas/administración & dosificación , Hipertensión/etiología , Hipertensión/metabolismo , Hipertensión/fisiopatología , Masculino , Bulbo Raquídeo/efectos de los fármacos , Bulbo Raquídeo/fisiopatología , Microinyecciones , Antagonistas de Narcóticos/administración & dosificación , Presión , Ratas , Ratas Sprague-Dawley , Receptor de Colecistoquinina A/antagonistas & inhibidores , Receptor de Colecistoquinina A/metabolismo , Sincalida/administración & dosificación , Factores de Tiempo
6.
Int J Pharm ; 450(1-2): 138-44, 2013 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-23623791

RESUMEN

LXT-101, a cationic peptide is a novel antagonist of gonadotropin-releasing hormone (GnRH) for prostate cancer treatment. However, effective delivery of peptide drugs into the body by the oral route remains a major challenge due to their origin properties with high molecular weights, strong polarity and low stability in the gastrointestinal (GI) tract. In this study, we have developed a novel oral delivery of oil-based formulation in which therapeutic peptide LXT-101 are solubilized in oils and with this solution as oil phase, an optimum formulation of self-microemulsifying drug delivery system (SMEDDS) was developed. The peptide stability with the SMEDDS formulation in artificial gastric and intestinal fluid was tested in vitro. On the other hand, the testosterone level and plasma concentration of LXT-101 in rats after oral administration of the SMEDDS formulation were investigated in vivo. The data in vitro indicated that LXT-101 in the SMEDDS formulation was stable over 8 h in artificial gastric and intestinal fluid. LXT-101 can be absorbed in vivo and suppression of testosterone maintained in castration level within 12 h can be achieved effectively after SMEDDS formulation administered orally at a dose of 3.5 mg/kg. The approach can provide a potential way for delivery peptides by oral.


Asunto(s)
Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Antagonistas de Hormonas/administración & dosificación , Oligopéptidos/administración & dosificación , Administración Oral , Animales , Aceite de Ricino/química , Castración , Antagonistas de Hormonas/química , Antagonistas de Hormonas/farmacocinética , Masculino , Oligopéptidos/química , Oligopéptidos/farmacocinética , Pancreatina/química , Pepsina A/química , Fosfatidilcolinas/química , Fosfatidilgliceroles/química , Propilenglicol/química , Neoplasias de la Próstata/tratamiento farmacológico , Ratas , Ratas Wistar , Testosterona/sangre
7.
Cardiovasc Pathol ; 22(5): 357-67, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23478013

RESUMEN

BACKGROUND: The possibility of decreasing or reverting left ventricular hypertrophy and, therefore, cardiac hypertrophy (CH) is an important medical issue. The aim of the present study was to evaluate these two possibilities with a 3-week daily dose of captopril, losartan, or bromocriptine in a preventive or corrective model. METHODS: After aorto caval fistulae (ACF) surgery on adult male Wistar rats to induce CH, animals were assigned to the preventive protocol (drug treatment began immediately after surgery) or corrective protocol (hypertrophy was allowed to develop before drug treatment). After treatments, isoproterenol was administered to half of the animals to further induce CH. The groups included the passive control, the sham-operated animals, those with ACF surgery but without drug treatment, and the 3-week treatments with captopril, losartan, or the low or high dose of bromocriptine. RESULTS: Three treatments, with captopril, losartan, or the high dose of bromocriptine, significantly impeded/reverted an increase in CH-related parameters in the preventive/corrective model compared to the surgically treated group without drug treatment. The same effect was found after isoproterenol administration. The present results show an avoidance/reversion of CH with these three treatments. Better results were found with the angiotensin converting enzyme inhibitor (captopril) than with the prolactin inhibitor (bromocriptine). CONCLUSIONS: Treatments with captopril, losartan, and the high dose of bromocriptine were effective in preventing/reversing the manifestation of CH in the preventive/corrective rat models. Further studies are needed to identify the initial mediator, the key component, and the molecular events involved in the pathogenesis of CH.


Asunto(s)
Cardiomegalia/prevención & control , Prolactina/antagonistas & inhibidores , Animales , Enfermedades de la Aorta/complicaciones , Fístula Arteriovenosa/complicaciones , Presión Sanguínea/efectos de los fármacos , Bromocriptina/administración & dosificación , Captopril/administración & dosificación , Cardiomegalia/tratamiento farmacológico , Cardiomegalia/patología , Modelos Animales de Enfermedad , Antagonistas de Hormonas/administración & dosificación , Humanos , Hipertrofia Ventricular Izquierda/tratamiento farmacológico , Hipertrofia Ventricular Izquierda/patología , Hipertrofia Ventricular Izquierda/prevención & control , Losartán/administración & dosificación , Masculino , Ratas , Ratas Wistar , Vena Cava Inferior
8.
Am J Physiol Gastrointest Liver Physiol ; 303(4): G519-28, 2012 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-22651925

RESUMEN

Because of the difficulties in developing suitable animal models, the pathogenesis of stress-induced functional gastrointestinal disorders is not well known. Here we applied the communication box technique to induce psychological stress in rats and then examined their gastrointestinal motility. We measured upper and lower gastrointestinal motility induced by acute and chronic psychological stress and examined the mRNA expression of various neuropeptides in the hypothalamus. Chronic psychological stress disrupted the fasted motility in the antrum and accelerated motility in the proximal colon. mRNA expression of AVP, oxytocin, and urocortin 3 was increased by chronic psychological stress. Intracerebroventricular (ICV) injection of urocortin 3 disrupted the fasted motility in the antrum, while ICV injection of Ucn3 antiserum prevented alteration in antral motility induced by chronic psychological stress. ICV injection of AVP accelerated colonic motility, while ICV injection of SSR 149415, a selective AVP V1b receptor antagonist, prevented alteration in proximal colonic motility induced by chronic psychological stress. Oxytocin and its receptor antagonist L 371257 had no effect on colonic motility in either the normal or chronic psychological stress model. These results suggest that chronic psychological stress induced by the communication box technique might disrupt fasted motility in the antrum via urocortin 3 pathways and accelerates proximal colonic motility via the AVP V1b receptor in the brain.


Asunto(s)
Arginina Vasopresina/metabolismo , Colon/inervación , Hormona Liberadora de Corticotropina/metabolismo , Enfermedades Gastrointestinales/etiología , Motilidad Gastrointestinal , Hipotálamo/metabolismo , Antro Pilórico/inervación , Estrés Psicológico/complicaciones , Urocortinas/metabolismo , Animales , Antagonistas de los Receptores de Hormonas Antidiuréticas , Arginina Vasopresina/administración & dosificación , Arginina Vasopresina/genética , Hormona Liberadora de Corticotropina/administración & dosificación , Hormona Liberadora de Corticotropina/genética , Modelos Animales de Enfermedad , Duodeno/inervación , Ayuno , Enfermedades Gastrointestinales/genética , Enfermedades Gastrointestinales/metabolismo , Enfermedades Gastrointestinales/fisiopatología , Motilidad Gastrointestinal/efectos de los fármacos , Antagonistas de Hormonas/administración & dosificación , Hipotálamo/efectos de los fármacos , Hipotálamo/fisiopatología , Sueros Inmunes/administración & dosificación , Indoles/administración & dosificación , Inyecciones Intraventriculares , Masculino , Manometría , Oxitocina/administración & dosificación , Oxitocina/metabolismo , Presión , Pirrolidinas/administración & dosificación , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores de Vasopresinas/metabolismo , Estrés Psicológico/genética , Estrés Psicológico/metabolismo , Estrés Psicológico/fisiopatología , Factores de Tiempo , Regulación hacia Arriba , Urocortinas/administración & dosificación , Urocortinas/genética
9.
Endocr J ; 59(7): 547-54, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22484995

RESUMEN

Neuropeptide W (NPW) was isolated as an endogenous ligand for NPBWR1, an orphan G protein-coupled receptor localized in the rat brain, including the paraventricular nucleus. It has been reported that central administration of NPW stimulates corticosterone secretion in rats. We hypothesized that NPW activates the hypothalamic-pituitary-adrenal (HPA) axis via corticotrophin-releasing factor (CRF) and/or arginine vasopressin (AVP). NPW at 1 pM to 10 nM did not affect basal or ACTH-induced corticosterone release from dispersed rat adrenocortical cells, or basal and CRF-induced ACTH release from dispersed rat anterior pituitary cells. In conscious and unrestrained male rats, intravenous administration of 2.5 and 25 nmol NPW did not affect plasma ACTH levels. However, intracerebroventricular (icv) administration of 2.5 and 5.0 nmol NPW increased plasma ACTH levels in a dose-dependent manner at 15 min after stimulation (5.0 vs. 2.5 nmol NPW vs. vehicle: 1802 ± 349 vs. 1170 ± 204 vs. 151 ± 28 pg/mL, respectively, mean ± SEM). Pretreatment with astressin, a CRF receptor antagonist, inhibited the increase in plasma ACTH levels induced by icv administration of 2.5 nmol NPW at 15 min (453 ± 176 vs. 1532 ± 343 pg/mL, p<0.05) and at 30 min (564 ± 147 vs. 1214 ± 139 pg/mL, p<0.05) versus pretreatment with vehicle alone. However, pretreatment with [1-(ß-mercapto-ß, ß-cyclopentamethylenepropionic acid), 2-(Ο-methyl)tyrosine]-arg-vasopressin, a V1a/V1b receptor antagonist, did not affect icv NPW-induced ACTH release at any time (p>0.05). In conclusion, we suggest that central NPW activates the HPA axis by activating hypothalamic CRF but not AVP.


Asunto(s)
Hormona Adrenocorticotrópica/metabolismo , Arginina Vasopresina/fisiología , Hormona Liberadora de Corticotropina/fisiología , Neuropéptidos/farmacología , Hormona Adrenocorticotrópica/sangre , Animales , Antagonistas de los Receptores de Hormonas Antidiuréticas , Células Cultivadas , Corticosterona/metabolismo , Evaluación Preclínica de Medicamentos , Antagonistas de Hormonas/administración & dosificación , Antagonistas de Hormonas/farmacología , Inyecciones Intravenosas , Masculino , Neuropéptidos/administración & dosificación , Adenohipófisis/citología , Adenohipófisis/efectos de los fármacos , Adenohipófisis/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores de Hormona Liberadora de Corticotropina/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Regulación hacia Arriba/efectos de los fármacos
10.
PLoS One ; 6(2): e16377, 2011 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-21359208

RESUMEN

Corticotropin-releasing factor (CRF) signaling pathways are involved in the stress response, and there is growing evidence supporting hair growth inhibition of murine hair follicle in vivo upon stress exposure. We investigated whether the blockade of CRF receptors influences the development of hair loss in CRF over-expressing (OE)-mice that display phenotypes of Cushing's syndrome and chronic stress, including alopecia. The non-selective CRF receptors antagonist, astressin-B (5 µg/mouse) injected peripherally once a day for 5 days in 4-9 months old CRF-OE alopecic mice induced pigmentation and hair re-growth that was largely retained for over 4 months. In young CRF-OE mice, astressin-B prevented the development of alopecia that occurred in saline-treated mice. Histological examination indicated that alopecic CRF-OE mice had hair follicle atrophy and that astressin-B revived the hair follicle from the telogen to anagen phase. However, astressin-B did not show any effect on the elevated plasma corticosterone levels and the increased weights of adrenal glands and visceral fat in CRF-OE mice. The selective CRF2 receptor antagonist, astressin2-B had moderate effect on pigmentation, but not on hair re-growth. The commercial drug for alopecia, minoxidil only showed partial effect on hair re-growth. These data support the existence of a key molecular switching mechanism triggered by blocking peripheral CRF receptors with an antagonist to reset hair growth in a mouse model of alopecia associated with chronic stress.


Asunto(s)
Alopecia/tratamiento farmacológico , Alopecia/prevención & control , Hormona Liberadora de Corticotropina/genética , Fragmentos de Péptidos/farmacología , Fragmentos de Péptidos/uso terapéutico , Alopecia/genética , Animales , Hormona Liberadora de Corticotropina/administración & dosificación , Hormona Liberadora de Corticotropina/farmacología , Hormona Liberadora de Corticotropina/uso terapéutico , Evaluación Preclínica de Medicamentos , Femenino , Cabello/efectos de los fármacos , Cabello/crecimiento & desarrollo , Antagonistas de Hormonas/administración & dosificación , Antagonistas de Hormonas/farmacología , Antagonistas de Hormonas/uso terapéutico , Inyecciones Intraperitoneales , Inyecciones Subcutáneas , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Fragmentos de Péptidos/administración & dosificación , Receptores de Hormona Liberadora de Corticotropina/antagonistas & inhibidores , Regulación hacia Arriba
11.
Am J Perinatol ; 28(6): 449-60, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21170825

RESUMEN

Preterm birth, the leading cause of neonatal morbidity and mortality, is estimated at incidence of 12.7% of all births, which has not decreased over the last four decades despite intensive antenatal care programs aimed at high-risk groups, the widespread use of tocolytics, and a series of other preventive and therapeutic interventions. Oxytocin antagonists, namely atosiban, represent an appealing choice that seems to be effective with apparently fewer side effects than the traditional tocolytics. This article reviews the available literature on the pharmacokinetics, mode of administration, and clinical utility of oxytocin antagonists for acute and maintenance tocolysis with special emphasis on its safety profile.


Asunto(s)
Antagonistas de Hormonas/uso terapéutico , Oxitocina/antagonistas & inhibidores , Nacimiento Prematuro/prevención & control , Tocolíticos/uso terapéutico , Vasotocina/análogos & derivados , Femenino , Antagonistas de Hormonas/administración & dosificación , Antagonistas de Hormonas/farmacocinética , Humanos , Indoles/uso terapéutico , Nifedipino/uso terapéutico , Oligopéptidos/uso terapéutico , Pirrolidinas/uso terapéutico , Simpatomiméticos/uso terapéutico , Tocolíticos/administración & dosificación , Tocolíticos/farmacocinética , Vasotocina/administración & dosificación , Vasotocina/farmacocinética , Vasotocina/uso terapéutico
12.
Reprod Biol Endocrinol ; 8: 51, 2010 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-20482803

RESUMEN

BACKGROUND: Reproductive function following chemotherapy is of increasing importance given that survival rates are improving. We assessed whether a gonadotropin-releasing hormone antagonist (GnRHant; cetrorelix) could promote ovarian protection against damage due to chemotherapy. METHODS: Forty-two female Wistar rats were used in this study. Animals were divided into four groups: group I (n=9) received placebo twice; group II (n=12) received placebo+cyclophosphamide (CPA); group III (n=12) received GnRHant+CPA; and group IV (n=9) received GnRHant+placebo. After medication, the estrous cycle was studied through vaginal smears. Rats were mated, pregnancy was documented and the number of live pups evaluated. Afterwards, rat ovaries were removed and prepared for histological studies. The ovarian cross-sectional area was measured and follicles were counted. RESULTS: Cyclic changes in vaginal smears were observed in all but one animal after treatment, but group II had a significantly lower rate of animals with proestrus or estrus (p<0.01). The offspring was markedly reduced by CPA treatment (group II, 3.00+/-1.33 pups vs. group I, 11.44+/-0.78 pups, p<0.01) and this effect was partly reversed by pre-treatment with GnRHant (group III, 7.00+/-1.31 pups). The ovarian cross-sectional area was not significantly different between groups, neither was the number of individual follicle types. However, rats in Group IV had a higher total number of ovarian follicles than those in the control group (17.1+/-1.22 vs. 10.9+/-0.70, p<0.05). CONCLUSION: The use of a GnRHant before CPA chemotherapy provided protection of fertility.


Asunto(s)
Ciclofosfamida/efectos adversos , Fertilidad/efectos de los fármacos , Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Antagonistas de Hormonas/uso terapéutico , Infertilidad Femenina/prevención & control , Ovario/efectos de los fármacos , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Recuento de Células , Ciclofosfamida/administración & dosificación , Ciclofosfamida/uso terapéutico , Esquema de Medicación , Evaluación Preclínica de Medicamentos , Femenino , Hormona Liberadora de Gonadotropina/administración & dosificación , Hormona Liberadora de Gonadotropina/análogos & derivados , Hormona Liberadora de Gonadotropina/uso terapéutico , Antagonistas de Hormonas/administración & dosificación , Infertilidad Femenina/inducido químicamente , Neoplasias/tratamiento farmacológico , Neoplasias/rehabilitación , Ovario/citología , Placebos , Embarazo , Índice de Embarazo , Ratas , Ratas Wistar
13.
J Bone Miner Metab ; 28(1): 49-54, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-19548062

RESUMEN

Cinacalcet, an allosteric modulator of a calcium (Ca)-sensing receptor, significantly suppresses parathyroid hormone (PTH) secretion and bone turnover rate in chronic hemodialysis (HD) patients with secondary hyperparathyroidism (SHPT). In this study, bone metabolism after cinacalcet treatment was examined, because hungry bone syndrome is sometimes experienced after parathyroidectomy in severe SHPT. We conducted a prospective observational study in 17 HD patients with SHPT. Cinacalcet was started at 25 mg/day, and the dose was increased step by step based on serum calcium level. A significant decrease in serum Ca and intact PTH concentration was found within 2 weeks. Tartrate-resistant acid phosphatase 5b, a good bone resorption marker, was significantly decreased at week 2 of the study. Serum bone alkaline phosphatase, a marker of bone formation, was increased at week 2 compared with the basal level. It became, however, gradually decreased until week 14. Only one patient whose bone turnover was considerably high had a mild numbness feeling. These results suggest that cinacalcet treatment might transiently accelerate bone formation with rapid suppression of bone resorption. This uncoupling could be involved in a mechanism by which cinacalcet decreases serum Ca level.


Asunto(s)
Remodelación Ósea/efectos de los fármacos , Huesos/efectos de los fármacos , Huesos/metabolismo , Antagonistas de Hormonas/farmacología , Hiperparatiroidismo Secundario/metabolismo , Naftalenos/farmacología , Hormona Paratiroidea/antagonistas & inhibidores , Fosfatasa Ácida/sangre , Fosfatasa Alcalina/sangre , Biomarcadores/sangre , Regeneración Ósea/efectos de los fármacos , Resorción Ósea/prevención & control , Calcio/sangre , Cinacalcet , Esquema de Medicación , Femenino , Antagonistas de Hormonas/administración & dosificación , Antagonistas de Hormonas/efectos adversos , Humanos , Hiperparatiroidismo Secundario/sangre , Hiperparatiroidismo Secundario/terapia , Isoenzimas/sangre , Masculino , Persona de Mediana Edad , Naftalenos/administración & dosificación , Naftalenos/efectos adversos , Hormona Paratiroidea/sangre , Fósforo/sangre , Diálisis Renal , Fosfatasa Ácida Tartratorresistente , Factores de Tiempo
14.
Fertil Steril ; 91(3): 744-8, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18321491

RESUMEN

OBJECTIVE: To explain the unexpected low response to GnRH antagonist protocol in reproductive women with normal baseline hormone profiles. DESIGN: Retrospective study. SETTING: University hospital. PATIENT(S): Twenty-five women undergoing their first IVF cycle. INTERVENTION(S): Follicular fluid (FF) from large follicles (>15 mm) was obtained during oocyte retrieval from unexpected low responders (n = 13, group A) and 12 age-matched normal responders (n = 12, group B). MAIN OUTCOME MEASURE(S): The FF markers known to reflect follicle environment (insulin-like growth factor [IGF] II, IGF-binding protein 4, müllerian-inhibiting substance, pregnancy-associated plasma protein A, soluble Fas, and vascular endothelial growth factor [VEGF]) were analyzed by ELISA. RESULT(S): The baseline characteristics (age, day 3 serum LH, FSH, E(2), duration and dose of r-FSH, GnRH antagonist) were not different between the two groups. The number of large follicles, oocytes retrieved, and serum E(2) levels on the day of hCG injection were significantly higher in group B. Whereas the other follicular markers did not differ between the two groups, VEGF was significantly higher in group A. In addition, the VEGF concentration showed an inverse correlation with the total number of oocytes retrieved. CONCLUSION(S): The unexpected low response in women with normal basal hormone profiles, during GnRH antagonist protocol, was associated with altered follicular VEGF expression.


Asunto(s)
Fármacos para la Fertilidad Femenina/administración & dosificación , Fertilización In Vitro , Líquido Folicular/metabolismo , Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Antagonistas de Hormonas/administración & dosificación , Hormonas/sangre , Inducción de la Ovulación/métodos , Factor A de Crecimiento Endotelial Vascular/metabolismo , Adulto , Gonadotropina Coriónica/administración & dosificación , Estradiol/sangre , Femenino , Hormona Folículo Estimulante Humana/administración & dosificación , Hormona Folículo Estimulante Humana/sangre , Hormona Liberadora de Gonadotropina/administración & dosificación , Hormona Liberadora de Gonadotropina/análogos & derivados , Humanos , Hormona Luteinizante/sangre , Recuperación del Oocito , Pancuronio/administración & dosificación , Pancuronio/análogos & derivados , Embarazo , Índice de Embarazo , Progesterona/sangre , Estudios Retrospectivos , Resultado del Tratamiento
15.
Neuro Endocrinol Lett ; 29(6): 857-66, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19112416

RESUMEN

In this case presentation, a woman with breast carcinoma who chose to try Prof. L. DiBella's biological therapy (MDB), was found, after seven months, to have a 50% reduction in objective measures of her carcinoma and was totally cured after 14 months. The patient's recovery extended to bilateral axillary adenopathies, and took place without the toxicity normally associated with cancer treatment. MDB entails the use of anti-proliferative molecules such as somatostatine, prolactin, and estrogen inhibitors, along with differentiating and apoptotic molecules such as melatonin, retinoids, vitamins C, D3, and E, calcium, and amino-sugars, combined with minimal doses of chemotherapy. The hemato-chemical exams showed no damage, with a progressive reduction of prolactin, estradiol, IGF1, and maintenance of low levels of GH. The achievement of objective results, without toxicity, in this case, proves the effectiveness of this therapy and confirms the positive results already published on the use of MDB for Low-Grade NHL, and pulmonary carcinomas in the 3rd and 4th stages. MDB, without the need for either hospitalization or day hospitalization, without toxicity, and without even minimally reducing the patient's daily work routine, allowed the patient to avoid surgical trauma and the significant collateral effects of chemo- and radiotherapy. Timely use of MDB as the first line therapy, in a patient which had not been debilitated by the mutagenic, toxic, and immuno-depressive effects of chemo- and radiotherapy, contributed greatly to the final outcome. We feel it is useful to highlight this case in an effort to stimulate interest and further study into the oncological potential of MDB biological and receptor therapy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/terapia , Carcinoma Ductal de Mama/terapia , Terapias Complementarias , Neoplasias Primarias Múltiples/terapia , Terapia Biológica/métodos , Femenino , Antagonistas de Hormonas/administración & dosificación , Humanos , Persona de Mediana Edad , Inducción de Remisión/métodos
16.
Brain Res Bull ; 75(5): 698-705, 2008 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-18355649

RESUMEN

Although the frequency-dependent antinociceptive mechanisms of electroacupuncture (EA) have been well demonstrated, the anti-inflammatory mechanisms that underlie the suppressive effects induced by different frequencies of EA stimulation on peripheral inflammation are largely unknown. We have previously reported that EA stimulation can activate the sympathetic nervous system (SNS) and that this activation is responsible for the EA-induced suppression of zymosan-induced leukocyte migration. The present study was designed to evaluate the differential effect of low (1Hz, LF EA) versus high (120Hz, HF EA) frequency EA stimulation on SNS activation and ultimately on carrageenan-induced inflammation. Immediately after carrageenan injection, we applied either LF EA or HF EA bilaterally to the Zusanli (ST36) acupoints. To evaluate the anti-inflammatory effect of EA (EA-AI), paw volume and myeloperoxidase (MPO) activity, a marker of infiltrated leukocytes, were measured and the paw withdrawal latency to noxious heat stimulation was also assessed. Both LF EA and HF EA significantly suppressed the carrageenan-induced paw edema and MPO activity. Moreover, thermal hyperalgesia was strongly attenuated in both the LF EA and HF EA groups. Adrenalectomy significantly diminished HF EA-AI without affecting LF EA-AI. Pretreatment with the corticosterone receptor antagonist, RU-486 did not affect either LF EA- or HF EA-AI. On the other hand, administration of 6-hydroxydopamine (a neurotoxin for peripheral sympathetic nerve endings) selectively blocked LF EA-AI. Propranolol (a beta-adrenoceptor antagonist) completely abolished both LF EA- and HF EA-AI. The results of this study suggest that the suppressive effects of LF EA on carrageenan-induced paw inflammation are mediated by sympathetic post-ganglionic neurons, while the suppressive effects of HF EA are mediated by the sympatho-adrenal medullary axis.


Asunto(s)
Médula Suprarrenal/fisiología , Estimulación Eléctrica/métodos , Electroacupuntura/métodos , Ganglios Simpáticos/patología , Inflamación/patología , Inflamación/terapia , Neuronas/efectos de la radiación , Médula Suprarrenal/efectos de la radiación , Adrenalectomía , Adrenérgicos/administración & dosificación , Animales , Carragenina , Modelos Animales de Enfermedad , Relación Dosis-Respuesta en la Radiación , Edema/inducido químicamente , Edema/patología , Antagonistas de Hormonas/administración & dosificación , Inflamación/inducido químicamente , Masculino , Ratones , Ratones Endogámicos ICR , Mifepristona/administración & dosificación , Neuronas/fisiología , Umbral del Dolor/efectos de los fármacos , Umbral del Dolor/fisiología , Umbral del Dolor/efectos de la radiación , Peroxidasa/metabolismo , Factores de Tiempo
17.
Biol Psychiatry ; 63(4): 360-8, 2008 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-17716630

RESUMEN

BACKGROUND: Both corticotropin-releasing factor (CRF) and glucocorticoid receptors (GR) are implicated in the psychotic symptoms of psychiatric disorders. Correspondingly, it is of interest to determine their respective involvement in the sensorimotor gating deficits displayed by transgenic mice overexpressing CRF. These mice reveal lifelong elevations of CRF and corticosterone levels. METHODS: Effects of the GR antagonists ORG34517 (5-45 mg/kg by mouth [PO]) and mifepristone (5-45 mg/kg PO) and the CRF(1) receptor antagonists CP154,526 (20-80 mg/kg intraperitoneally [IP]) and DMP695 (2.5-40.0 mg/kg IP) on prepulse inhibition (PPI) of the acoustic startle response were studied in mice overexpressing CRF and in their wild-type littermates. In addition, PPI was measured in both genotypes 2 weeks after adrenalectomy with or without exogenous corticosterone administration via subcutaneous pellet implant (20 mg corticosterone). RESULTS: ORG34517 and mifepristone did not influence perturbation of PPI in mice overexpressing CRF; reducing corticosterone levels by adrenalectomy likewise did not improve PPI. Further, elevation in corticosterone levels by pellet implantation did not disrupt PPI in wild-type mice. Conversely, both CRF(1) receptor antagonists, CP154,526 (40-80 mg/kg IP) and DMP695 (40 mg/kg IP), significantly restored PPI in CRF-overexpressing mice. CONCLUSIONS: Sustained overactivation of CRF(1) receptors rather than excessive GR receptor stimulation underlies impaired sensorimotor gating in CRF-overexpressing mice. CRF(1) receptors thus may play a role in the expression of psychotic features in stress-related psychiatric disorders.


Asunto(s)
Benzodioxoles/farmacología , Expresión Génica , Trastornos Psicóticos/tratamiento farmacológico , Trastornos Psicóticos/genética , Receptores de Hormona Liberadora de Corticotropina/antagonistas & inhibidores , Receptores de Hormona Liberadora de Corticotropina/genética , Receptores de Glucocorticoides/antagonistas & inhibidores , Esteroides/farmacología , Estimulación Acústica , Adrenalectomía , Animales , Benzodioxoles/administración & dosificación , Trastorno Depresivo Mayor/tratamiento farmacológico , Trastorno Depresivo Mayor/genética , Modelos Animales de Enfermedad , Genotipo , Antagonistas de Hormonas/administración & dosificación , Antagonistas de Hormonas/farmacología , Infusiones Parenterales , Masculino , Ratones , Ratones Transgénicos , Mifepristona/administración & dosificación , Mifepristona/farmacología , Reflejo de Sobresalto , Esteroides/administración & dosificación
18.
Eur J Neurosci ; 25(12): 3702-12, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17610589

RESUMEN

It is well known that initial consolidation requires de novo gene transcription and protein synthesis in order for memory to become stable. The consolidated memory again becomes labile and temporarily sensitive to disruption when retrieved, requiring a reconsolidation process to become permanent. Although it is well established that glucocorticoid receptors (GR) in the basolateral nucleus of amygdala (BLA) are required for consolidation of fear memory, little is known about their role in reconsolidation of fear memory. In the present study, we first examined the effect of a GR antagonist on postconditioning consolidation of auditory fear memory (AFM). Intra-BLA infusion of the GR antagonist RU486 0 h postconditioning impaired long-term AFM, leaving short-term AFM intact. RU486 had no effect if infusion was performed 6 h postconditioning. We then investigated the effect of the RU486 treatment on postretrieval reconsolidation of AFM. Severe amnesia took place when RU486 was infused into the BLA 0 h postretrieval (reactivation) of AFM, regardless of whether the retrieval was performed 1 day or 10 days postconditioning. RU486 produced no amnesia if the memory retrieval was omitted or if the drug was administered 6 h postretrieval. Treatment with RU486 0 h postretrieval produced no deficit in postretrieval short-term memory but impaired postretrieval long-term memory, and the amnesia exhibited no spontaneous recovery 6 days after retrieval. The present results provide strong evidence that glucocorticoid receptors in the BLA are required for reconsolidation as well as consolidation of AFM.


Asunto(s)
Estimulación Acústica/efectos adversos , Amígdala del Cerebelo/metabolismo , Condicionamiento Clásico/fisiología , Miedo , Memoria/fisiología , Receptores de Glucocorticoides/fisiología , Animales , Conducta Animal/efectos de los fármacos , Mapeo Encefálico , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Antagonistas de Hormonas/administración & dosificación , Masculino , Mifepristona/administración & dosificación , Ratas , Ratas Sprague-Dawley , Factores de Tiempo
19.
Am J Vet Res ; 67(12): 1998-2005, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17144800

RESUMEN

OBJECTIVE: To measure plasma cholecystokinin (CCK) activity and the effect of a CCK-1 receptor antagonist on accommodation of the proximal portion of the stomach, and subsequent gastric emptying, in horses after ingestion of high-fat or high-carbohydrate meals. ANIMALS: 6 healthy adult horses with gastric cannulas. PROCEDURES: In the first study, horses were offered a high-fat (8% fat) or a high-carbohydrate (3% fat) pelleted meal of identical volume, caloric density, and protein content. Related plasma CCK-like activity was measured by radioimmunoassay (RIA). In a separate experiment, a horse was fed a grain meal with corn oil and phenylalanine, and plasma CCK activity was assessed by bioassay. A second study evaluated the effect of a CCK-1 receptor antagonist, devazepide (0.1 mg/kg, IV), on gastric accommodation and emptying following a meal of grain supplemented with either corn oil (12.3% fat) or an isocaloric amount of glucose (2.9% fat). Gastric tone was measured by a barostat and emptying by the (13)C-octanoic acid breath test. RESULTS: No plasma CCK-like activity was detected by RIA or bioassay before or after ingestion of meals. Preprandial devazepide did not alter the gastric accommodation response but did significantly shorten the gastric half-emptying time and time to peak breath (13)CO(2) content with the glucose-enriched meal. CONCLUSIONS AND CLINICAL RELEVANCE: In horses, CCK participates in regulating the gastric motor response to a meal. Compared with other species, horses may be more responsive to carbohydrate than fat. A vagovagal reflex most likely mediates this regulation, with CCK as a paracrine intermediary at the intestinal level.


Asunto(s)
Colecistoquinina/fisiología , Vaciamiento Gástrico/fisiología , Caballos/fisiología , Estómago/fisiología , Alimentación Animal , Animales , Isótopos de Carbono/análisis , Colecistoquinina/sangre , Devazepida/administración & dosificación , Devazepida/farmacología , Carbohidratos de la Dieta/administración & dosificación , Grasas de la Dieta/administración & dosificación , Femenino , Vaciamiento Gástrico/efectos de los fármacos , Antagonistas de Hormonas/administración & dosificación , Antagonistas de Hormonas/farmacología , Isótopos de Yodo/análisis , Masculino , Relajación Muscular/efectos de los fármacos , Distribución Aleatoria , Receptores de Colecistoquinina/antagonistas & inhibidores , Factores de Tiempo
20.
Toxicol Sci ; 72(2): 296-300, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12660364

RESUMEN

Genistein is a plant-derived estrogenic isoflavone commonly found in soy-based products such as soymilk and soy-based dietary supplements for treating menopausal symptoms, for example. Vasopressin is a neurosecretory nonapeptide synthesized primarily in neurons of the hypothalamus and secreted into the bloodstream from the posterior lobe of the pituitary. The endogenous opiate peptide beta-endorphin is synthesized both in neurons of the hypothalamus and in pituitary cells, primarily of the neurointermediate lobe. It has been reported that exposure to 17beta-estradiol or diethylstilbesterol increased the vasopressin content of the hypothalamus, and that estradiol valerate selectively damages hypothalamic beta-endorphin-containing neurons. Since little was known of the potential effects of estrogenic endocrine-disruptor compounds on hypothalamic neuropeptides, we fed Sprague-Dawley fetuses from day 7 in utero until sacrifice at postnatal day 77, with either a control diet (<1 ppm) or an experimental diet containing 25, 250, or 1250 ppm of genistein. We then conducted ELISA assays for hypothalamic content of both beta-endorphin and vasopressin immunoreactivity. Whereas there were no statistically reliable effects of dietary genistein on hypothalamic beta-endorphin content, vasopressin levels were significantly elevated in the 1250-ppm genistein group (p < 0.05). Elevated vasopressin levels may be associated with fluid balance, altered blood pressure, and cardiovascular effects. These data are consistent with the known actions of estradiol and may serve to explain our finding in a previous study that estrogenic endocrine-disruptors such as genistein increased sodium preference in rats exposed through their diet.


Asunto(s)
Genisteína/toxicidad , Antagonistas de Hormonas/toxicidad , Hipotálamo/efectos de los fármacos , Vasopresinas/metabolismo , betaendorfina/metabolismo , Animales , Relación Dosis-Respuesta a Droga , Femenino , Antagonistas de Hormonas/administración & dosificación , Hipotálamo/metabolismo , Masculino , Exposición Materna , Embarazo , Efectos Tardíos de la Exposición Prenatal , Ratas , Ratas Sprague-Dawley
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