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1.
Nutr Neurosci ; 19(9): 414-422, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25763920

RESUMEN

OBJECTIVES: Undernutrition during development alters the expression of peptides that control energy expenditure and feeding behavior. Estrogens can also modulate these peptides. Here, we analyze whether the early postnatal administration of estradiol modulates the effects of undernutrition on neuroendocrine parameters in adult female Wistar rats. METHODS: Control rats were fed a control diet. Undernourished pups were submitted to a restricted diet with half of the undernourished rats receiving 0.4 mg/kg s.c. of estradiol benzoate (EB) from postnatal day (P) 6 until P13. Quantitative real-time polymerase chain reaction was performed to determine expression in the hypothalamus of agouti-related peptide (AgRP), proopiomelanocortin (POMC), neuropeptide Y (NPY), and cocaine- and amphetamine-regulated transcript. Plasma estradiol, testosterone, and adiponectin levels were measured by enzyme-linked immunosorbent assay. Total and acylated ghrelin levels were measured in plasma by radioimmunoassay. Insulin and leptin were measured by mulitplex immunoassays. RESULTS: Undernourishment decreased body weight, fat mass, plasma leptin and insulin levels, and hypothalamic POMC mRNA levels. An increase in orexigenic signals AgRP and NPY mRNA levels, and in plasma adiponectin levels were found in undernourished animals. Early postnatal treatment with EB to undernourished female rats reversed the effects of undernutrition on adult hypothalamic POMC mRNA levels. In addition, neonatal EB treatment to undernourished females significantly decreased adult plasma testosterone, estradiol, and acylated ghrelin levels. DISCUSSION: Our results suggest that increased estradiol during a critical period of development has the capacity to modulate the alterations that undernutrition produces on energy metabolism.


Asunto(s)
Estradiol/análogos & derivados , Estrógenos/administración & dosificación , Retardo del Crecimiento Fetal/fisiopatología , Hipotálamo/efectos de los fármacos , Desnutrición/etiología , Fenómenos Fisiologicos Nutricionales Maternos , Deficiencia de Proteína/fisiopatología , Animales , Dieta con Restricción de Proteínas/efectos adversos , Susceptibilidad a Enfermedades , Estradiol/administración & dosificación , Femenino , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Hipotálamo/metabolismo , Hipotálamo/patología , Inyecciones Subcutáneas , Lactancia , Desnutrición/metabolismo , Desnutrición/patología , Desnutrición/fisiopatología , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Neuronas/patología , Embarazo , Deficiencia de Proteína/etiología , Distribución Aleatoria , Ratas Wistar , Destete , Aumento de Peso/efectos de los fármacos
2.
Ann Rheum Dis ; 74(11): 1946-57, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26245755

RESUMEN

To develop evidence based points to consider the use of imaging in the diagnosis and management of juvenile idiopathic arthritis (JIA) in clinical practice. The task force comprised a group of paediatric rheumatologists, rheumatologists experienced in imaging, radiologists, methodologists and patients from nine countries. Eleven questions on imaging in JIA were generated using a process of discussion and consensus. Research evidence was searched systematically for each question using MEDLINE, EMBASE and Cochrane CENTRAL. Imaging modalities included were conventional radiography, ultrasound, MRI, CT, scintigraphy and positron emission tomography. The experts used the evidence obtained from the relevant studies to develop a set of points to consider. The level of agreement with each point to consider was assessed using a numerical rating scale. A total of 13 277 references were identified from the search process, from which 204 studies were included in the systematic review. Nine points to consider were produced, taking into account the heterogeneity of JIA, the lack of normative data and consequent difficulty identifying pathology. These encompassed the role of imaging in making a diagnosis of JIA, detecting and monitoring inflammation and damage, predicting outcome and response to treatment, use of guided therapies, progression and remission. Level of agreement for each proposition varied according to the research evidence and expert opinion. Nine points to consider and a related research agenda for the role of imaging in the management of JIA were developed using published evidence and expert opinion.


Asunto(s)
Artritis Juvenil/diagnóstico , Articulaciones , Adolescente , Comités Consultivos , Artritis Juvenil/terapia , Niño , Preescolar , Manejo de la Enfermedad , Humanos , Articulaciones/diagnóstico por imagen , Articulaciones/patología , Imagen por Resonancia Magnética , Tomografía de Emisión de Positrones , Radiografía , Cintigrafía , Reumatología , Tomografía Computarizada por Rayos X , Ultrasonografía
3.
Int J Sports Med ; 35(11): 933-8, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24886929

RESUMEN

Different pacing profiles have been identified in the literature for endurance sporting events: the 'positive', 'negative', 'even', 'parabolic shaped' and 'variable pacing'. Most studies have focused on competitive or elite athletes (including winners) without considering more recreational runners, for many of whom the primary goal is simply to finish the event. The major city marathons provide a large heterogeneous sample to compare the pacing profiles of competitive vs. recreational runners, and thus to understand pacing more broadly. A total of 190,228 New York finishers' (69,316 women) marathon times (from 2006 to 2011) were assessed. Although all runners developed a positive pace profile, a lower variability of speed through the race was found in the top runners (coefficient of variation (CV) for speed during 5-km splits: 7.8% (men) and 6.6% (women)) compared with the less successful runners (CV ranging from 8.3 to 14.4%). Both men and women try to maintain an even pace profile along the marathon course, partly by avoiding an excessively fast start that might result in a pronounced decrease in the speed in the second half of the race.


Asunto(s)
Resistencia Física/fisiología , Carrera/fisiología , Conducta Competitiva/fisiología , Femenino , Humanos , Masculino , Ciudad de Nueva York , Aptitud Física/fisiología , Factores Sexuales
4.
Ann Rheum Dis ; 67(7): 1017-22, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17921183

RESUMEN

OBJECTIVE: To develop education guidelines for the conduct of future European League Against Rheumatism (EULAR) musculoskeletal ultrasound (MSUS) courses. METHODS: We undertook a consensus-based, iterative process using two consecutive questionnaires sent to 29 senior ultrasonographer rheumatologists who comprised the faculty of the 14th EULAR ultrasound course (June 2007). The first questionnaire encompassed the following issues: type of MSUS educational model; course timing; course curriculum; course duration; number of participants per teacher in practical sessions; time spent on hands-on sessions; and the requirements and/or restrictions for attendance at the courses. The second questionnaire consisted of questions related to areas where consensus had not been achieved in the first questionnaire, and to the topics and pathologies to be assigned to different educational levels. RESULTS: The response rate was 82.7% from the first questionnaire and 87.5% from the second questionnaire. The respondents were from 11 European countries. The group consensus on guidelines and curriculum was for a three-level education model (basic, intermediate and advanced) with timing and location related to the annual EULAR Congresses. The topics and pathologies to be included in each course were agreed. The course duration will be 20 h. There will be a maximum of six participants per teacher and 50-60% of total time will be spent on practical sessions. There was also agreement on prerequisite experience before attending the intermediate and advanced courses. CONCLUSION: We have developed European agreed guidelines for the content and conduct of EULAR ultrasound courses, which may also be recommended to national and local MSUS training programmes.


Asunto(s)
Educación Médica/organización & administración , Enfermedades Musculoesqueléticas/diagnóstico por imagen , Radiología/educación , Reumatología/educación , Actitud del Personal de Salud , Curriculum , Educación Médica/normas , Europa (Continente) , Humanos , Cooperación Internacional , Modelos Educacionales , Encuestas y Cuestionarios , Ultrasonografía
5.
Horm Behav ; 54(4): 557-64, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18582470

RESUMEN

The neuronal nitric oxide synthase (nNOS) is involved in the control of male and female sexual behavior and its distribution in several regions of the limbic-hypothalamic system, as well as its coexistence with gonadal hormones' receptors, suggests that these hormones may play a significant role in controlling its expression. However, data illustrating the role of gonadal hormones in controlling the nNOS expression are, at present, contradictory, even if they strongly suggest an involvement of testosterone (T) in the regulation of nNOS. The action of T may be mediated through androgen (AR) or, after aromatization to estradiol (E(2)), through estrogen receptors. To elucidate the role of AR on nNOS expression, we compared male and female rats with a non-functional mutation of AR (Tfm, testicular feminization mutation) to their control littermates. We investigated some hypothalamic and limbic nuclei involved in the control of sexual behavior [medial preoptic area (MPA), paraventricular (PVN), arcuate (ARC), ventromedial (VMH) and stria terminalis (BST) nuclei]. In BST (posterior subdivision), VMH (ventral subdivision), and MPA we detected a significant sexual dimorphism in control animals and a decrease of nNOS positive elements in Tfm males compared to their littermate. In addition, we observed a significant increase of nNOS positive elements in BST (posterior) of Tfm females. No significant changes were observed in the other nuclei. These data indicate that, contrary to current opinions, androgens, through the action of AR may have a relevant role in the organization and modulation of the nNOS hypothalamic system.


Asunto(s)
Hipotálamo/metabolismo , Sistema Límbico/metabolismo , Óxido Nítrico Sintasa de Tipo I/metabolismo , Receptores Androgénicos/fisiología , Virilismo/metabolismo , Síndrome de Resistencia Androgénica/genética , Síndrome de Resistencia Androgénica/metabolismo , Andrógenos/fisiología , Animales , Animales Modificados Genéticamente , Femenino , Sistema Límbico/fisiología , Masculino , Modelos Biológicos , Ratas , Ratas Wistar , Receptores Androgénicos/metabolismo , Diferenciación Sexual/fisiología
6.
Pediatr Rheumatol Online J ; 16(1): 23, 2018 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-29631610

RESUMEN

BACKGROUND: Recently preliminary ultrasonography (US) definitions, in B mode, for normal components of pediatric joints have been developed by the OMERACT US group. The aim of the current study was to include Doppler findings in the evaluation and definition of normal joint features that can be visualized in healthy children at different age groups. METHODS: A multistep approach was used. Firstly, new additional definitions of joint components were proposed during an expert meeting. In the second step, these definitions, along with the preliminary B-mode-US definitions, were tested for feasibility in an exercise in healthy children at different age groups. In the last step, a larger panel of US experts were invited to join a web-based consensus process in order to approve the developed definitions using the Delphi methodology. A Likert scale of 1-5 was used to assess agreement. RESULTS: Physiological vascularity and fat pad tissue were identified and tested as two additional joint components in healthy children. Since physiological vascularity changes over the time in the growing skeleton, the final definition of Doppler findings comprised separate statements instead of a single full definition. A total of seven statements was developed and included in a written Delphi questionnaire to define and validate the new components. The final definitions for fat pad and physiological vascularity agreed by the group of experts reached 92.9% and 100% agreement respectively in a web survey. CONCLUSION: The inclusion of these two additional joints components which are linked to detection of Doppler signal in pediatric healthy joints will improve the identification of abnormalities in children with joint pathologies.


Asunto(s)
Articulaciones/diagnóstico por imagen , Ultrasonografía Doppler/métodos , Adolescente , Niño , Preescolar , Consenso , Técnica Delphi , Humanos
7.
Clin Exp Rheumatol ; 25(6): 915-21, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18173930

RESUMEN

OBJECTIVE: To describe or determine reference values for the intracapsular cavity and its joint recess of the hip, knee and joints of the hand and for the tendon sheaths of fingers, examined with B-mode gray-scale ultrasonography (US) and power Doppler (PD) in healthy children. METHODS: Sixty healthy children (31 boys and 29 girls; age range 2-16 years) were examined bilaterally with gray-scale and PD US (after obtaining the informed consent), using a standardized technique. The maximum distance from bone surface to the outer margin of the capsule (namely, intracapsular cavity) and its joint recess of hip, knee, wrist, non-thumb metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints of the hand were measured with US. Mean values +/- 2 SD (standard deviation) were indicated as reference values. RESULTS: None of the children showed joint hip fluid. In 5% of the children younger than 5 years an intra-capsular PD flow signal was detected in the posterior layer of the hip capsule. Fluid was detected in 60 % of the suprapatellar recesses. A small amount of fluid was detected within synovial recesses of the fingers, most commonly in the 2 MCP and PIP joints. Less frequently, a hypoechoic rim was detected around the finger flexor tendons on the palmar surface of the metacarpal bone. CONCLUSION: High-resolution US evidences a normal small amount of fluid located at the MCP and IFP joint recesses and/or the flexor tendon sheaths without any PD flow signal in healthy children, that is relevant for interpreting ultrasonographic findings in children with inflammatory diseases.


Asunto(s)
Articulaciones/diagnóstico por imagen , Tendones/diagnóstico por imagen , Adolescente , Niño , Preescolar , Femenino , Articulaciones de los Dedos/diagnóstico por imagen , Articulación de la Cadera/diagnóstico por imagen , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Masculino , Articulación Metacarpofalángica/diagnóstico por imagen , Variaciones Dependientes del Observador , Ultrasonografía Doppler , Articulación de la Muñeca/diagnóstico por imagen
8.
Neuroscience ; 138(3): 987-95, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16310319

RESUMEN

Nitric oxide-containing neurons are widely distributed within the CNS, including regions involved in the control of reproduction and sexual behavior. The expression of neuronal nitric oxide synthase is influenced by testosterone in male rat, and by estrogens in female. Moreover, nitric oxide synthase may co-localize with gonadal hormones' receptors. Gonadal hormones may influence nitric oxide synthase expression in adulthood as well as during the development. In fact, in mice knockout for estrogen receptor alpha, the nitric oxide synthase-expressing population is deeply reduced in specific regions. In physiological conditions, the female in mammalian species is exposed to short-term changes of gonadal hormones levels (estrous cycle). Our recent studies, performed in the rat vomeronasal system and in mouse hypothalamic and limbic systems reveal that, in rodents, the expression of nitric oxide synthase-producing elements within regions relevant for the control of sexual behavior is under the control of gonadal hormones. The expression of nitric oxide synthase may vary according to the rapid variations of hormonal levels that take place during the estrous cycle. This seems in accordance with the hypothesis that gonadal hormone activation of nitric oxide-cyclic guanosine-monophosphate pathway is important for lordosis behavior, as well as that this system is activated during mating behavior. Finally, comparative data available for other vertebrates suggest that class-specific and species-specific differences occur in the nitric oxide synthase system of hypothalamus and limbic structures. Therefore, particular caution is needed to generalize data obtained from studies in rodents.


Asunto(s)
Andrógenos/fisiología , Encéfalo/fisiología , Estrógenos/fisiología , Óxido Nítrico/fisiología , Conducta Sexual Animal , Animales , Femenino , Masculino , Ratones , Óxido Nítrico/biosíntesis , Óxido Nítrico Sintasa de Tipo I/metabolismo , Ratas , Reproducción
9.
Farm Hosp ; 30(1): 33-43, 2006.
Artículo en Español | MEDLINE | ID: mdl-16569182

RESUMEN

OBJECTIVE: To review the maximum stability of thermolabile drugs at room temperature (22-25 degrees C) in order to quickly act in case of breakage of the cold chain. METHOD: The study included all drugs available in the pharmacy service from August 17, 2004 to October 15 of the same year, date in which the review was performed, that had to be kept at a temperature ranging between 2 degrees and 8 degrees C. Different drug laboratories were contacted and asked for written information on the matter. RESULTS: The results are reported in a table. One hundred seventy three medicinal products including 83 drugs were reviewed. CONCLUSIONS: Some information provided by the pharmaceutical industry allows the use of drugs even when the cold chain has been broken. This information must be used only in isolated cases, not as a routine.


Asunto(s)
Estabilidad de Medicamentos , Temperatura , Refrigeración
10.
J Comp Neurol ; 376(2): 315-25, 1996 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-8951646

RESUMEN

Steroid-sensitive, vocal courtship behavior is a function of a specific, hypothalamic nucleus, the sexually dimorphic area pars compacta (SDApc) in the male adult gerbil. Gender-related differences in the number of neurons in this nucleus are evident immediately after birth. By using unbiased stereological estimates of cell numbers in Nissl-stained, paraffin-wax sections of brain, we investigated the mechanisms differentiating cell number between the sexes in the SDApc on postnatal days 0, 3, 6, and 15. Cell death, identified by pyknosis, was greatest in the SDApc between days 0-3 in males, whereas in females, maximum values were reached between days 3-6. Similarly, the ratio of pyknotic to normal neurons peaked between days 0-3 in males and 3-6 in females but then declined in both sexes. Pyknotic cells were seldom seen in either sex by day 15. Morphological characteristics of apoptosis including chromatin condensation, cell fragmentation, and ingestion of apoptic bodies by macrophages were all demonstrated by transmission electron microscopy. Macrophages showed specific morphological characteristics of microglia. Cell division (mitosis) was identified in the SDApc during postnatal days 0, 3, and 6 but the numbers of mitotic figures were low, negligible on day 15, and similar between the sexes. These results demonstrate that cell death and proliferation occur simultaneously in the neonatal gerbil brain. The stereological estimates of cell death in the developing SDApc indicated a lower incidence of neuronal death occurring earlier in males than in females.


Asunto(s)
Gerbillinae/anatomía & histología , Neuronas/citología , Área Preóptica/crecimiento & desarrollo , Caracteres Sexuales , Sustancia Negra/crecimiento & desarrollo , Vocalización Animal/fisiología , Animales , Apoptosis , Recuento de Células , División Celular , Femenino , Gerbillinae/crecimiento & desarrollo , Masculino , Morfogénesis , Área Preóptica/citología , Sustancia Negra/citología
11.
Biochem Pharmacol ; 40(11): 2519-24, 1990 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-2268370

RESUMEN

The effect of exhaustive exercise on the hepatobiliary transport of organic anions was investigated in rats. Animals were run on a rodent treadmill at 24 m/min up a 12% grade (152 +/- 15 min). Exercise resulted in significant hypoglycaemia (-46%) and increased plasma levels of lactate (+12%), together with a marked reduction of glycogen concentration in the liver (-72%). When bromosulphthalein was administered i.v., its maximal biliary excretion (Tm) was significantly reduced (-30%), and plasma and liver concentrations of the dye were increased (+31% and +56%, respectively). The decrease corresponded both to the excretion of the conjugated and unconjugated dye (-30% and -33%, respectively). Cytosolic glutathione S-transferase activity in the liver was not affected by exercise, but there was a significant reduction in the hepatic concentration of glutathione (-50%). The Tm of dibromosulphthalein was also significantly reduced (-36%) and its plasma and liver concentrations increased (+67% and +33%, respectively) in exercised rats. The results suggest that, in addition to the direct effect of liver glutathione depletion, other factors must be involved in the impairment of the biliary excretion of organic anions caused by exercise.


Asunto(s)
Bilis/metabolismo , Esfuerzo Físico , Animales , Glutatión/metabolismo , Hígado/metabolismo , Circulación Hepática , Masculino , Ratas , Ratas Endogámicas , Sulfobromoftaleína/metabolismo
12.
Biochem Pharmacol ; 37(18): 3461-5, 1988 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-3421996

RESUMEN

The effect of the antianginal agent perhexiline maleate (160 mg/kg i.g., daily for 4 days) on the biliary excretion of sulfobromophthalein (BSP) and BSP-glutathione and the hepatic activity of glutathione S-transferases was investigated in Wistar rats. Perhexiline maleate caused a significant reduction in the maximal biliary excretion of BSP (-28%). The decrease corresponded to a lowered excretion of the conjugated dye whereas the excretion of the parent compound did not change significantly. Administration of the drug caused no effect on the maximal biliary excretion of infused BSP-glutathione. Liver glutathione concentrations were similar in control and treated rats. Perhexiline maleate significantly reduced liver glutathione S-transferase activities toward BSP (-25%), 3,4-dichloronitrobenzene (DCNB) (-21%) and 1-chloro-3,4-dinitrobenzene (DNCB) (-27%). Kinetic studies of the enzyme in liver cytosol showed that perhexiline maleate induced an uncompetitive inhibition for the BSP substrate with a reduced Vmax and Km. The results indicate that the reduction in glutathione S-transferase activity plays an important role as a factor determining the impairment in the hepatobiliary transport of BSP caused by perhexiline maleate.


Asunto(s)
Bilis/efectos de los fármacos , Glutatión Transferasa/antagonistas & inhibidores , Perhexilina/análogos & derivados , Sulfobromoftaleína/metabolismo , Animales , Bilis/metabolismo , Glutatión/metabolismo , Cinética , Hígado/enzimología , Masculino , Perhexilina/farmacología , Ratas , Ratas Endogámicas
13.
Neuroreport ; 9(11): 2653-6, 1998 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-9721950

RESUMEN

It has been hypothesized that the vomeronasal system (VNS), a complex neural network implicated in the control of reproductive behaviors, is sexually dimorphic. The posteromedial cortical amygdaloid nucleus (PMCo) belongs to the group of amygdaloid structures that receive direct olfactory input from the accessory olfactory bulb. In the present study we looked for sex differences in this nucleus in male and female adult rats and we found that the males had larger volumes and more neurons than the females. These results support the hypothesis that the VNS is a sexually dimorphic system.


Asunto(s)
Amígdala del Cerebelo/anatomía & histología , Amígdala del Cerebelo/citología , Amígdala del Cerebelo/fisiología , Animales , Recuento de Células , Femenino , Masculino , Neuronas/fisiología , Vías Olfatorias/anatomía & histología , Vías Olfatorias/citología , Vías Olfatorias/fisiología , Ratas , Ratas Wistar , Caracteres Sexuales
14.
Neuroreport ; 3(4): 327-9, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1387557

RESUMEN

In the present study the regulatory action of the non-aromatic androgen dihydrotestoterone (DHT) on the volume of the sexually dimorphic bed nucleus of the accessory olfactory tract (BAOT) was investigated. Postnatal treatment with DHT (180 micrograms day-1) between days 6 and 20 (D6-D20) induced, in gonadally intact male rats, a drastic reduction in the overall volume to levels typical in control females. Conversely, the postnatal administration of the anti-androgen cyproterone acetate (CA) to the females from D6-D20 produced an increment in the BAOT volume not dissimilar to that found in control males. These findings reveal that sexual organization in this vomeronasal structure is dependent on the presence of DHT in females during postnatal development.


Asunto(s)
Antagonistas de Andrógenos/farmacología , Ciproterona/análogos & derivados , Dihidrotestosterona/farmacología , Vías Olfatorias/fisiología , Animales , Ciproterona/farmacología , Acetato de Ciproterona , Femenino , Masculino , Vías Olfatorias/citología , Vías Olfatorias/efectos de los fármacos , Ratas , Ratas Endogámicas , Caracteres Sexuales
15.
Brain Res ; 694(1-2): 167-76, 1995 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-8974641

RESUMEN

Display of a specific, courtship vocalization and other masculine functions in the adult gerbil, is associated with a sexually differentiated hypothalamic nucleus, the Sexually Dimorphic Area pars compacta (SDApc). Total SDApc volume and vocal function differentiate neonatally. Since total volume is a rudimentary measure of brain nucleus differentiation, we examined the more detailed cytoarchitectural parameters behind SDApc development in gerbils, cell number, density per nucleus and individual nuclear (soma) volume. Unbiased stereological estimates were made on thick (20-40 microm) brain sections from postnatal days 1 (D1), 3 (133), 6 (DO, 16 (D16), 40 (D40) and 60 (D60) animals. Sex differences in stereological parameters were not apparent on D1 but from D3, SDApc growth patterns widely differed between the sexes. Significant differences in (i) cell number, and (ii) nuclear volume were found at D3 and D60, respectively. In males, cell number increased between D1-D6 but subsequently decreased from the D6 value by approximately 80% to reach the value of D16 which remained constant. Cell density paralleled the decrease in cell number between D6-D16 in males, whereas a progressive expansion in nuclear volume occurred between D1-D40. Male total SDApc volume enlarged between D1-D3 and D40-D60. Conversely in females, cell number and density declined between D1-D3 and D1-D40, respectively, and then remained at these low values. Cell volume, however, increased up to D40 and then significantly decreased. The resulting change to female total SDApc volume was a reduction immediately after birth, D1-D3, to a constant low value. We conclude that first, the association between various stereological measures and total SDApc volume was minimal, suggesting independent mechanisms of sexual differentiation for each cytoarchitectonic parameter. Second, the neonatal peak in SDApc cell number indicates cell migration taking place contemporaneously with cell death in males. Third, the effect of changes in cytoarchitectural components between D6-D16 and D40-D60 in males is probably due to SDApc dendritic volume expansion, suggesting that the male SDApc retains plasticity until at least puberty. Fourth, the decrease in the number of cells in females early in neonatal life, suggests programmed cell death.


Asunto(s)
Animales Recién Nacidos/crecimiento & desarrollo , Gerbillinae/crecimiento & desarrollo , Hipotálamo/crecimiento & desarrollo , Caracteres Sexuales , Vocalización Animal/fisiología , Animales , Recuento de Células , Núcleo Celular/ultraestructura , Hipotálamo/citología , Hipotálamo/ultraestructura , Métodos
16.
Brain Res Dev Brain Res ; 109(1): 99-108, 1998 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-9706395

RESUMEN

In the present study, we investigate the development of sex differences in the bed nucleus of the accessory olfactory tract (BAOT), a sexually dimorphic structure in which masculinization of male rats depends on the level of postnatal estradiol. Male and female Wistar rats were sacrificed postnatally when they were 1, 3, 7, 15, 45 and 60 days old, and stereological methods were used to estimate the volume and number of neurons in the BAOT of the subjects. With respect to volume, sex differences were established from P15. In relation to the number of neurons, the males acquire their adult morphological parameter by P15, while females show a decrease (P3), increase (from P3 to P15) and later decrease (from P15 to P45). Sex differences from P3 to P7 might be related to greater cell death in the BAOT of the females. These results support the hypothesis that both male and female rats reach their adult morphological pattern within this sexually dimorphic nucleus in an active manner.


Asunto(s)
Bulbo Olfatorio/crecimiento & desarrollo , Animales , Apoptosis/fisiología , Recuento de Células , Femenino , Masculino , Neuronas/citología , Bulbo Olfatorio/citología , Ratas , Ratas Wistar , Caracteres Sexuales
17.
Brain Res Dev Brain Res ; 56(2): 263-8, 1990 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-2261686

RESUMEN

This work investigates the existence of sex differences in the volume and number of neurons and glial cells in the bed nucleus of the accessory olfactory tract (BAOT). Males showed larger volume and number of cells than female rats. Early postnatal (day 1 after birth) orchidectomy in males, and androgenization in females, reversed these differences. No sex differences were found in BAOT glial cells. The sexual dimorphism found in the neuron/glial cell ratio reflects sex differences in neuron number. The existence of sexual dimorphism in the BAOT supports our earlier hypothesis which states that the vomeronasal system (VNS) is sexually dimorphic.


Asunto(s)
Vías Olfatorias/citología , Orquiectomía , Testosterona/farmacología , Animales , Femenino , Masculino , Neuroglía/citología , Neuroglía/efectos de los fármacos , Neuronas/citología , Neuronas/efectos de los fármacos , Vías Olfatorias/efectos de los fármacos , Ratas , Ratas Endogámicas , Valores de Referencia , Factores Sexuales
18.
Brain Res Dev Brain Res ; 68(1): 132-5, 1992 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-1521319

RESUMEN

The regulatory action of the non-aromatizable androgen dihydrotestosterone (DHT) on sexual differentiation of the volume of the rat accessory olfactory bulb (AOB) was studied. Postnatal treatment with DHT (180 micrograms/day) carried out daily between days 6 and 20 produced a drastic reduction in overall AOB size and that of its constituent neural layers in genetic males with respect to intact and control males. The volumetric measures found in DHT-treated males did not differ from those shown by the intact females. These results, which indicate a demasculinization and a feminization of the AOB volume in gonadally intact male rats induced by DHT, are discussed in relation to the presumably regulatory role of DHT on neuron populations during the sexual organizational process of the brain.


Asunto(s)
Dihidrotestosterona/farmacología , Bulbo Olfatorio/efectos de los fármacos , Caracteres Sexuales , Animales , Femenino , Masculino , Bulbo Olfatorio/crecimiento & desarrollo , Ratas , Ratas Endogámicas , Diferenciación Sexual/efectos de los fármacos
19.
Brain Res Dev Brain Res ; 75(2): 285-7, 1993 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-8261617

RESUMEN

Orchidectomized males injected with a single dose of estradiol benzoate (EB) on the day of birth (D1) showed a volume and neuron number in the nucleus of the accessory olfactory tract (BAOT) similar to that of control males. However, orchidectomized males and those orchidectomized and given a single dose of DHT on D1 showed a decrease in BAOT volume and neuron number with respect to control males. These results support the notion that estradiol induces the morphological masculinization of this structure. The inability of DHT in counteracting the effect of orchidectomy is addressed taking into account the inhibitory action of androgens.


Asunto(s)
Estradiol/farmacología , Vías Olfatorias/crecimiento & desarrollo , Caracteres Sexuales , Animales , Dihidrotestosterona/farmacología , Femenino , Masculino , Vías Olfatorias/anatomía & histología , Vías Olfatorias/efectos de los fármacos , Orquiectomía , Ratas , Ratas Wistar
20.
Neurosci Lett ; 184(2): 86-9, 1995 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-7724052

RESUMEN

Hypothalamic neuroglial ontogeny was examined during neonatal development of two hormone-sensitive, sex-specific nuclei, the pars compacta of the sexually dimorphic area (SDApc) and the suprachiasmatic nucleus (SCN) in the gerbil. Specific antibodies against vimentin and glial fibrillary acidic proteins (GFAP) identified neuroglia. Unbiased measures of labelled cell anatomical parameters were taken using stereomorphometric techniques. High numbers of cells in the female and male SCN immunoreacted with vimentin in neonates and GFAP in adults. Astrocytes containing vimentin or GFAP were few in number in the SDApc and surrounding areas in neonates and adults, respectively. There was a sex difference in the numerical density of both vimentin and GFAP-positive cells in the SCN. We suggest that (a) pre-astroglia are involved in gender-related organization of the SCN but not in SDApc, and (b) neuroglia have a sex-related, functional role in the mature SCN.


Asunto(s)
Astrocitos/fisiología , Hipotálamo/citología , Envejecimiento/fisiología , Animales , Femenino , Gerbillinae , Proteína Ácida Fibrilar de la Glía/metabolismo , Histocitoquímica , Hipotálamo/anatomía & histología , Hipotálamo/crecimiento & desarrollo , Masculino , Caracteres Sexuales , Núcleo Supraquiasmático/citología , Núcleo Supraquiasmático/crecimiento & desarrollo , Núcleo Supraquiasmático/fisiología , Vimentina/metabolismo
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