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1.
Endocrinology ; 136(11): 4858-63, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7588217

RESUMEN

To examine the physiological role of cholinergic input in the regulation of CRF neurons in the paraventricular nucleus (PVN) of the hypothalamus, acetylcholine (ACh) was microinjected bilaterally into the dorsolateral border of the PVN of conscious rats. Changes in the levels of POMC messenger RNA (mRNA) in the anterior pituitary, CRF mRNA in hypothalamic tissue containing the PVN, and plasma ACTH were assessed. Plasma ACTH concentrations increased in a dose-dependent manner after ACh injection (1-100 pmol/side), reaching a peak 30 min after ACh injection and returning to baseline within 120 min. The POMC mRNA level in the anterior pituitary and the hypothalamic CRF mRNA level increased in a dose-dependent manner 120 min after ACh (0.1-10 pmol/side) injection. Intracerebroventricular pretreatment with atropine completely abolished the ACh-induced increase in plasma ACTH concentrations, whereas pretreatment with hexamethonium was without significant effect. The intracerebroventricular injection of ACh also increased plasma ACTH concentrations in a dose-dependent manner in conscious rats, but not in pentobarbital-anesthetized animals. Thus, cholinergic hypothalamic input stimulates CRF gene expression in the PVN and CRF secretion into the portal circulation under physiological conditions. The use of conscious animals is essential in elucidating the physiological roles of neurotransmitters and other modulators regulating CRF neurons.


Asunto(s)
Acetilcolina/farmacología , Hormona Liberadora de Corticotropina/genética , Expresión Génica/efectos de los fármacos , Núcleo Hipotalámico Paraventricular/metabolismo , Acetilcolina/administración & dosificación , Hormona Adrenocorticotrópica/sangre , Animales , Atropina/farmacología , Northern Blotting , Antagonistas Colinérgicos , Relación Dosis-Respuesta a Droga , Hexametonio/farmacología , Cinética , Masculino , Microinyecciones , Parasimpatolíticos/farmacología , Núcleo Hipotalámico Paraventricular/efectos de los fármacos , Adenohipófisis/metabolismo , Proopiomelanocortina/genética , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Receptores Colinérgicos/fisiología
2.
Endocrinology ; 135(5): 2177-82, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7956940

RESUMEN

To examine the physiological effects of norepinephrine (NE) in the paraventricular nucleus of the hypothalamus (PVH) on CRF gene expression and CRF release, NE was microinjected bilaterally into the PVH of conscious rats, and kinetic studies were performed on the levels of POMC messenger RNA (mRNA) in the anterior pituitary (AP), CRF mRNA in the PVH-containing hypothalamic fragment, and plasma ACTH. Plasma ACTH levels were increased dose dependently by NE (5-50 nmol/side) injection into the PVH. They reached their peaks after 30 min and returned to the basal values after 90 min. The POMC mRNA level in the AP and hypothalamic CRF mRNA level increased significantly 90 min after NE injection and increased further after 120 min. The POMC mRNA level in the AP and hypothalamic CRF mRNA level were increased dose dependently by NE (5-50 nmol/side) after 120 min. Intracerebroventricular pretreatment with prazosin abolished completely the increase in plasma ACTH levels after intrahypothalamic NE injection, whereas pretreatment with propranolol was without significant effect. These results suggest that NE stimulates CRF gene expression in the PVH and CRF secretion into the portal circulation, thus regulating positively the hypothalamic-pituitary-adrenal axis. alpha 1-Adrenergic receptors may mediate the action of NE on CRF neurons.


Asunto(s)
Estado de Conciencia/fisiología , Hormona Liberadora de Corticotropina/genética , Norepinefrina/farmacología , Núcleo Hipotalámico Paraventricular/fisiología , Hormona Adrenocorticotrópica/sangre , Animales , Hormona Liberadora de Corticotropina/análisis , Hormona Liberadora de Corticotropina/metabolismo , Relación Dosis-Respuesta a Droga , Regulación de la Expresión Génica , Sistema Hipotálamo-Hipofisario/fisiología , Masculino , Microinyecciones , Núcleo Hipotalámico Paraventricular/química , Núcleo Hipotalámico Paraventricular/metabolismo , Adenohipófisis/química , Adenohipófisis/metabolismo , Sistema Hipófiso-Suprarrenal/fisiología , Proopiomelanocortina/análisis , Proopiomelanocortina/genética , ARN Mensajero/análisis , ARN Mensajero/genética , Ratas , Ratas Wistar , Factores de Tiempo
3.
Endocrinology ; 137(6): 2389-96, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8641191

RESUMEN

To assess whether the cAMP-dependent protein kinase-A and/or the diacylglycerol-dependent protein kinase C (PKC) pathways play important roles in the activation of CRF neurons in vivo under physiological conditions, we tested the effect of microinjection of 8-bromo-cAMP (8-Br-cAMP) or 12-O-tetradecanoyl phorbol 13-acetate (TPA) into both paraventricular nuclei (PVN) of the hypothalamus in conscious rats. Both 8-Br-cAMP and TPA increased plasma ACTH concentrations and the POMC messenger RNA (mRNA) concentrations in the anterior pituitary. While injection of 8-Br-cAMP also increased CRF mRNA concentrations in hypothalamic tissue containing the PVN, TPA injection had no effect on CRF mRNA concentrations there. During insulin-induced hypoglycemia, which stimulates CRF gene expression and release, c-fos and c-jun mRNA increases in the hypothalamic tissue preceded the increase in the CRF mRNA level after insulin-induced hypoglycemia. Antisense oligodeoxyribonucleotides (oligos) directed against c-fos, c-jun, or the cAMP response element binding protein (CREB) mRNA were injected into both PVN before insulin-induced hypoglycemia to assess whether activator protein-1 or CREB mediates transcriptional activation of CRF during hypoglycemia. Only antisense oligo against CREB mRNA reduced the CRF mRNA level after insulin-induced hypoglycemia. These results suggest that protein kinase A may transduce intracellular signals in CRF neurons under physiological conditions and raises the possibility that CREB may be involved in stress-induced CRF gene expression.


Asunto(s)
Hormona Liberadora de Corticotropina/genética , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , AMP Cíclico/farmacología , Expresión Génica , Hipotálamo/metabolismo , 8-Bromo Monofosfato de Adenosina Cíclica/administración & dosificación , 8-Bromo Monofosfato de Adenosina Cíclica/farmacología , Hormona Adrenocorticotrópica/sangre , Animales , Secuencia de Bases , Expresión Génica/efectos de los fármacos , Genes fos/genética , Genes jun/genética , Hipoglucemia/inducido químicamente , Hipoglucemia/metabolismo , Hipotálamo/efectos de los fármacos , Insulina , Masculino , Microinyecciones , Datos de Secuencia Molecular , Oligonucleótidos Antisentido/farmacología , Núcleo Hipotalámico Paraventricular/efectos de los fármacos , Núcleo Hipotalámico Paraventricular/metabolismo , Proopiomelanocortina/genética , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Acetato de Tetradecanoilforbol/farmacología
4.
Arch Neurol ; 41(10): 1091-4, 1984 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6477218

RESUMEN

The adult type of neuronal ceroid lipofuscinosis (NCL) occurred in a 49-year-old man and his 51-year-old sister. They showed episodic stuporous and psychotic states, mental retardation, generalized convulsions, and ichthyosis vulgaris. At autopsy the woman had excessive accumulation of lipofuscin throughout the CNS. The degree of neuronal lipopigment accumulation was very severe in the neurons of the thalamus, substantia nigra, inferior olivary nuclei, motor nuclei of the brain stem, and cerebral cortex. Mental symptoms, such as stupor, excitement, hallucinations, and delusions, were the predominant clinical manifestations and so were misdiagnosed as schizophrenia. Though the clinical diagnosis of the adult type of NCL (Kufs' disease) is difficult because of its wide variety of manifestations, symptoms such as episodic psychotic and stuporous states accompanied by convulsive disorders with mild neurologic signs may be an indication of this disease.


Asunto(s)
Lipofuscinosis Ceroideas Neuronales/genética , Factores de Edad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Lipofuscinosis Ceroideas Neuronales/patología
5.
J Mol Endocrinol ; 33(3): 639-49, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15591024

RESUMEN

Although corticotropin-releasing hormone (CRH) plays a pivotal role in the regulation of the hypothalamo-pituitary-adrenal axis, the mechanism of CRH gene expression in the neuronal cell is not completely understood. In this study, we examined the transcriptional regulation of human CRH gene 5'-promoter, using a human BE(2)C neuroblastoma cell line expressing intrinsic CRH. In particular, we focused on the involvement of calmodulin kinases (CaMKs), which are known to play an important role in excitation-induced gene expression through the rise in intracellular calcium in the central nervous system. RT-PCR analysis confirmed the expression of CaMK as well as CRH mRNA in BE(2)C cells. When we introduced approximately 1.1 kb of the 5'-promoter region of the human CRH fused with luciferase reporter gene into the cells, a substantial transcriptional activity was observed, and this was further increased by the activation of the cAMP/PKA pathway. We then examined the effect of activation of CaMKs by introducing the expression vectors of each kinase, revealing a potent stimulatory effect of CaMKIV, but no effect of CaMKII. Depolarization of the cells caused an increase in CRH promoter activity, which was completely abolished by the treatment with the CaMK antagonist K252a. Interestingly, KCREB, a dominant negative form of CREB, antagonized the effect of the CaMKIV-mediated effect. Altogether, we conclude that not only the cAMP/PKA but also the calcium/CaMKIV signaling pathway is involved in the regulation of CRH gene expression. Furthermore, CREB is thought to be involved in CaMK- as well as cAMP/PKA-mediated CRH gene expression. Since the CRH gene is expressed in the neuronal cells of the hypothalamus, the calcium/CaMKIV signaling pathway may play an important role in the excitation-mediated regulation of CRH synthesis.


Asunto(s)
Señalización del Calcio , Hormona Liberadora de Corticotropina/genética , Regulación de la Expresión Génica/genética , Neuronas/metabolismo , Regiones Promotoras Genéticas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Transcripción Genética/genética , Calcio/metabolismo , Señalización del Calcio/efectos de los fármacos , Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina , Línea Celular Tumoral , AMP Cíclico/química , AMP Cíclico/metabolismo , AMP Cíclico/farmacología , Proteína de Unión a Elemento de Respuesta al AMP Cíclico , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Activación Enzimática , Humanos , Potenciales de la Membrana/efectos de los fármacos , Potasio/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
6.
Neuropharmacology ; 33(2): 181-7, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7518572

RESUMEN

The effect of endogenous opioid receptor stimulation on the central cardiovascular and behavioral actions of substance P (SP) was examined in conscious rats. SP (55 pmol) injected intracerebroventricularly (i.c.v.) elicited increases in mean arterial pressure, heart rate, and stereotyped behavioral activation such as exploring and grooming, which were considered to be parts of the cardiovascular defense reaction. Intravenous (i.v.) pretreatment with morphine (2.5 and 5.0 mg/kg) attenuated the cardiovascular and behavioral responses produced by SP i.c.v. dose-dependently. The i.v. pretreatment with naloxone (10 mg/kg) had no effect on the central SP-induced response. Pressor responses elicited by i.c.v. injection of corticotropin-releasing factor or angiotensin II were also attenuated by pretreatment with i.v. morphine (5.0 mg/kg). Our results showed that endogenous opioid receptor stimulation antagonizes the central cardiovascular and behavioral actions of SP. Morphine may not influence the primary site of action of SP but does influence the central neural pathway which conveys the SP-induced sympathetic activation signal.


Asunto(s)
Conducta Animal/efectos de los fármacos , Sistema Cardiovascular/efectos de los fármacos , Morfina/farmacología , Sustancia P/farmacología , Análisis de Varianza , Animales , Presión Sanguínea/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Frecuencia Cardíaca/efectos de los fármacos , Masculino , Naloxona/farmacología , Ratas , Ratas Wistar , Sustancia P/administración & dosificación , Sustancia P/antagonistas & inhibidores
7.
J Hypertens ; 5(6): 749-53, 1987 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3429875

RESUMEN

To investigate the clinical usefulness of radio-immunoassay of neuropeptide Y (NPY), we measured plasma immunoreactive neuropeptide Y (IR-NPY) concentrations in normal subjects (n = 21), essential hypertensive patients (n = 33), patients with phaeochromocytoma (n = 7), patients with chronic renal disease with serum creatinine levels of less than 1.9 mg/dl (n = 5) and patients with chronic renal failure whose serum creatinine levels were greater than or equal to 1.9 mg/dl (n = 18, eight without haemodialysis and 10 undergoing maintenance haemodialysis), by radio-immunoassay. Plasma IR-NPY concentrations in patients with phaeochromocytoma (577 +/- 256 pg/ml, mean +/- s.d.) were significantly higher (P less than 0.001) than those in normal subjects (151 +/- 28 pg/ml), essential hypertensive patients (177 +/- 49 pg/ml) and patients with chronic renal disease with serum creatinine levels less than 1.9 mg/dl (198 +/- 71 pg/ml). Plasma IR-NPY concentrations in patients with chronic renal failure (without haemodialysis: 330 +/- 63 pg/ml; undergoing maintenance haemodialysis: 374 +/- 80 pg/ml) were also high. These results suggest that NPY is useful as one of the tumour markers of phaeochromocytomas. However, this study revealed that patients with chronic renal failure, without phaeochromocytoma also have increased plasma IR-NPY concentrations.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/sangre , Hipertensión/sangre , Fallo Renal Crónico/sangre , Neuropéptido Y/sangre , Feocromocitoma/sangre , Adulto , Cromatografía en Gel , Creatinina/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radioinmunoensayo , Diálisis Renal
8.
Neuroscience ; 87(2): 439-46, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9740403

RESUMEN

Nitric oxide and glucocorticoids have been implicated in learning and memory, as well as in regulation of the stress response. By use of the in situ hybridization technique, we examined the role of glucocorticoids in the regulation of nitric oxide synthase messenger RNA in the hippocampus. In control animals, nitric oxide synthase subtype I (neuronal) messenger RNA was expressed in the CA1, CA3 and dentate gyrus of the hippocampus. Nitric oxide synthase subtype I expression was almost absent in CA2 pyramidal neurons. Neither subtype II (immunological) nor subtype III (endothelial) nitric oxide synthase messenger RNAs were observed in neurons of the hippocampal subfields. Bilateral removal of the adrenal glands resulted in a significant increase in nitric oxide synthase subtype I messenger RNA expression in the CA1 and CA3 pyramidal neurons and in granular cells of the dentate gyrus. To a lesser degree, the nitric oxide synthase subtype I messenger RNA signal was increased in CA2 pyramidal neurons. Daily administration of glucocorticoids for one week attenuated the adrenalectomy-induced increased level of expression of the messenger RNA encoding nitric oxide synthase subtype I in all areas studied. Because adrenalectomy, which suppresses the production of glucocorticoids, increases nitric oxide synthase expression, and replacement of adrenalectomized animals with glucocorticoids restores the basal levels of nitric oxide synthase subtype I expression, our results demonstrate an up-regulation of nitric oxide synthase subtype I messenger RNA in the absence of glucocorticoids in the hippocampus. The present findings suggest an involvement of the stress axis in the regulation of the synaptic plasticity process mediated by nitric oxide in the hippocampus.


Asunto(s)
Glucocorticoides/fisiología , Hipocampo/metabolismo , Óxido Nítrico Sintasa/biosíntesis , ARN Mensajero/biosíntesis , Adrenalectomía , Animales , Antiinflamatorios/farmacología , Corticosterona/farmacología , Dexametasona/farmacología , Procesamiento de Imagen Asistido por Computador , Hibridación in Situ , Masculino , Óxido Nítrico Sintasa de Tipo I , Células Piramidales/enzimología , Ratas , Ratas Sprague-Dawley
9.
Br J Pharmacol ; 107(3): 750-5, 1992 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1335337

RESUMEN

1. The effects of intracerebroventricular (i.c.v.) pretreatment with selective NK1 ((+/-)-CP 96,345), NK2a (MEN 10,207; MEN 10,376) and NK2b (R 396) tachykinin receptor antagonists on the cardiovascular and behavioural responses to i.c.v. substance P (SP) and neurokinin A (NKA) were studied in conscious rats. 2. SP and NKA (25 pmol) induced mean arterial blood pressure and heart rate increases of the same magnitude and duration. The cardiovascular responses to both peptides were accompanied by excessive face washing, sniffing, grooming and wet dog shakes. 3. The cardiovascular responses to SP but not to NKA were attenuated by pretreatment with a NK1 receptor antagonist, (+/-)-CP 96,345. Of the behavioural responses, only face washing was significantly inhibited. 4. The cardiovascular and behavioural effects of NKA but not of SP were significantly attenuated by pretreatment with the selective NK2b receptor antagonist, R 396. 5. The selective NK2a receptor antagonists, MEN 10,207 and MEN 10,376, did not affect the cardiovascular and behavioural responses to either SP or NKA. 6. These results suggest, firstly, that the cardiovascular and behavioural effects of i.c.v. SP are mediated by NK1 receptors; secondly, that NKA injected i.c.v. does not interact with NK1 receptors but with another type of tachykinin receptor which may belong to the NK2b subclass. These findings provide pharmacological evidence for the existence of functionally active NK2 receptors in the rat brain.


Asunto(s)
Conducta Animal/efectos de los fármacos , Hemodinámica/efectos de los fármacos , Receptores de Neurotransmisores/antagonistas & inhibidores , Taquicininas/farmacología , Secuencia de Aminoácidos , Animales , Presión Sanguínea/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacos , Inyecciones Intraventriculares , Masculino , Datos de Secuencia Molecular , Neuroquinina A/análogos & derivados , Neuroquinina A/farmacología , Oligopéptidos/farmacología , Fragmentos de Péptidos/farmacología , Ratas , Ratas Wistar , Receptores de Taquicininas
10.
Brain Res Mol Brain Res ; 88(1-2): 62-73, 2001 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-11295232

RESUMEN

We have previously demonstrated that microinjection of norepinephrine (NE) into the paraventricular nucleus of the hypothalamus (PVN) of conscious rats elicits a marked increase in CRH gene transcription, indicated by CRH hnRNA levels, without changing AVP hnRNA levels. We hypothesized that this differential response is due to differential sensitivity of AVP and CRH gene transcription to the inhibitory effects of the NE-induced rise in corticosterone. In the current study, we used animals that had been adrenalectomized and implanted with a subcutaneous corticosterone pellet (ADX/B) which prevented the NE-induced rise in corticosterone levels. NE (50 nmol) or artificial CSF was injected into the PVN of conscious rats, which had undergone either sham-operation (SHAM) or ADX/B 1 week earlier. CRH and AVP hnRNA levels were semi-quantitated by in situ hybridization using intron-specific riboprobes. In both SHAM and ADX/B animals, CRH hnRNA levels were significantly elevated at the 15 min time-point and returned to basal levels by 120 min. At 15 min, the magnitude of the CRH hnRNA response was only slightly greater in the ADX/B group than SHAM. In contrast, changes in medial parvocellular PVN AVP hnRNA levels in the ADX/B group were significantly greater than the changes observed in the SHAM group, at both the 15 and 120 min time-points. These results suggest that corticosterone has a greater impact on the transcriptional regulation of AVP than CRH, suggesting important differences and distinct roles of these secretagogues in the regulation of the hypothalamic-pituitary-adrenal axis.


Asunto(s)
Antiinflamatorios/farmacología , Arginina Vasopresina/genética , Corticosterona/farmacología , Hormona Liberadora de Corticotropina/genética , Norepinefrina/farmacología , Núcleo Hipotalámico Paraventricular/fisiología , Simpatomiméticos/farmacología , Adrenalectomía , Hormona Adrenocorticotrópica/sangre , Animales , Antiinflamatorios/sangre , Corticosterona/sangre , Expresión Génica/efectos de los fármacos , Masculino , Microinyecciones , Núcleo Hipotalámico Paraventricular/efectos de los fármacos , ARN Nuclear Heterogéneo/análisis , ARN Mensajero/análisis , Ratas , Ratas Wistar , Transcripción Genética/efectos de los fármacos
11.
J Neuroendocrinol ; 16(4): 348-55, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15089973

RESUMEN

Tuberoinfundibular corticotropin-releasing hormone (CRH) neurones are the principal regulators of the hypothalamic-pituitary-adrenal (HPA)-axis. Vasopressin is primarily a neurohypophysial hormone, produced in magnocellular neurones of the hypothalamic paraventricular and supraoptic nuclei, but parvocellular CRH neurones also coexpress vasopressin, which acts as a second 'releasing factor' for adrenocorticotropic hormone along with CRH. All stress inputs converge on these hypothalamic neuroendocrine neurones, and the input signals are integrated to determine the output secretion of CRH and vasopressin. Aminergic, cholinergic, GABAergic, glutamatergic and a number of peptidergic inputs have all been implicated in the regulation of CRH/vasopressin neurones. Glucocorticoids inhibit the HPA-axis activity by negative feedback. Interleukin-1 stimulates CRH and vasopressin gene expression, and is implicated in immune-neuroendocrine regulation. cAMP-response element-binding protein phosphorylation may mediate transcriptional activation of both CRH and vasopressin genes, but the roles of AP-1 and other transcription factors remain controversial. Expression profiles of the CRH and vasopressin genes are not uniform after stress exposure, and the vasopressin gene appears to be more sensitive to glucocorticoid suppression.


Asunto(s)
Hormona Liberadora de Corticotropina/metabolismo , Hipotálamo/fisiología , Vasopresinas/genética , Animales , Expresión Génica
12.
Peptides ; 14(2): 365-9, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8483815

RESUMEN

Pituitary adenylate cyclase activating polypeptide (PACAP) is a novel hypothalamic peptide consisting of 38 amino acids [PACAP(1-38)] with a potent stimulatory action on adenylate cyclase in rat pituitary. The presence of immunoreactive (IR-) PACAP in the tumor tissue of pheochromocytomas was studied by radioimmunoassay and immunocytochemistry. The antibody to PACAP was raised in a rabbit injected with a peptide containing amino acids 28-38 of PACAP. This antibody showed no significant cross-reactivity with either PACAP(1-27) or vasoactive intestinal polypeptide. The tumor tissue concentrations of IR-PACAP(1-38) were 0.5-57.5 pmol/g wet weight (n = 13) (24.5 +/- 22.4 pmol/g wet weight, mean +/- SD), while those in the normal adrenal glands were 3.58 +/- 2.02 pmol/g wet weight (n = 7) and those in the adrenal cortical tumors were 5.58 +/- 2.02 pmol/g wet weight (n = 6). The IR-PACAP(1-38) concentrations in 7 out of 13 pheochromocytomas exceeded 18 pmol/g wet weight. Sephadex G-50 column chromatography revealed that the IR-PACAP(1-38) in extracts of pheochromocytomas eluted in both the positions of PACAP(1-38) and a larger molecular weight. Reverse-phase high performance liquid chromatography of the tumor extracts revealed a peak in the position of PACAP(1-38) and at least four other peaks. Immunocytochemistry of pheochromocytomas showed numerous immunoreactive cells. The immunostaining was abolished by absorption of the antiserum with synthetic PACAP(1-38). These findings indicate that multiple forms of IR-PACAP(1-38) are present in pheochromocytomas.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/metabolismo , Neuropéptidos/metabolismo , Feocromocitoma/metabolismo , Neoplasias de las Glándulas Suprarrenales/patología , Cromatografía en Gel , Cromatografía Líquida de Alta Presión , Humanos , Inmunohistoquímica , Feocromocitoma/patología , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa , Radioinmunoensayo
13.
Peptides ; 15(1): 37-40, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8015979

RESUMEN

The distribution and molecular form of C-type natriuretic peptide (CNP) in the human central nervous system were studied with a specific radioimmunoassay for CNP-22. Immunoreactive (IR-) CNP was detectable in all regions of the brain examined (cerebral cortex, thalamus, hypothalamus, pons, and cerebellum) (0.21-0.81 pmol/g wet tissue, n = 4). The highest concentration of IR-CNP was found in the spinal cord at 1.83 +/- 0.13 pmol/g wet tissue (mean +/- SD, n = 3). Reversed-phase high performance liquid chromatography revealed a major peak migrating at the position corresponding to synthetic human CNP-53 and minor peaks comigrating with synthetic CNP-22 and the methionine-oxidized form of CNP-22, respectively. These findings suggest that IR-CNP is widely present in the human central nervous system mainly in a high molecular weight form as the major component and in the molecular form of CNP-22 as the minor component.


Asunto(s)
Factor Natriurético Atrial/análisis , Sistema Nervioso Central/química , Proteínas del Tejido Nervioso/análisis , Anciano , Factor Natriurético Atrial/química , Cromatografía en Gel , Cromatografía Líquida de Alta Presión , Femenino , Humanos , Masculino , Péptido Natriurético Tipo-C , Proteínas del Tejido Nervioso/química , Radioinmunoensayo
14.
Peptides ; 12(6): 1333-5, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1815220

RESUMEN

The presence of immunoreactive porcine brain natriuretic peptide in rat tissues was studied with a specific radioimmunoassay for porcine brain natriuretic peptide-26. The cross-reactivity of the antiserum used was less than 0.001% with rat atrial natriuretic peptide, rat brain natriuretic peptide-32 and rat brain natriuretic peptide-45. Immunoreactive porcine brain natriuretic peptide was detectable in various tissues of the rat, and high concentrations of immunoreactive porcine brain natriuretic peptide were found in the brain and cardiac atrium, with the highest level in the hypothalamus (159 +/- 30 fmol/gram wet tissue, mean +/- SEM, n = 4). Reverse phase high performance liquid chromatography showed that the immunoreactive porcine brain natriuretic peptide of the whole brain and heart extracts eluted mainly at an identical position to synthetic porcine brain natriuretic peptide-26. These findings indicate that porcine brain natriuretic peptide-like substance, distinct from rat brain natriuretic peptide, is present in high concentrations in the rat brain and cardiac atrium.


Asunto(s)
Proteínas del Tejido Nervioso/metabolismo , Animales , Encéfalo/metabolismo , Cromatografía Líquida de Alta Presión , Masculino , Miocardio/metabolismo , Péptido Natriurético Encefálico , Radioinmunoensayo , Ratas , Ratas Endogámicas , Porcinos , Distribución Tisular
15.
Peptides ; 9(2): 433-5, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3287359

RESUMEN

Neuropeptide Y-like immunoreactivity (NPY-LI) in plasma during insulin-induced hypoglycemia was measured in 4 healthy male volunteers. Plasma NPY-LI increased from 167 +/- 11 pg/ml to 247 +/- 25 pg/ml 30 min after the administration of insulin (0.1 U/kg body weight IV), reached the maximum (296 +/- 6 pg/ml) 45 min after the insulin, and then decreased. These results suggest that NPY is released into the systemic circulation during insulin-induced hypoglycemia in man.


Asunto(s)
Hipoglucemia/sangre , Insulina/farmacología , Neuropéptido Y/sangre , Adulto , Glucemia/metabolismo , Humanos , Hipoglucemia/inducido químicamente , Cinética , Masculino , Valores de Referencia
16.
Peptides ; 13(1): 121-3, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1535705

RESUMEN

The presence of immunoreactive human brain natriuretic peptide in the human brain was studied with a specific radioimmunoassay for human brain natriuretic peptide-32. This assay showed no significant cross-reaction with human alpha atrial natriuretic peptide, porcine brain natriuretic peptide or rat brain natriuretic peptide. Immunoreactive human brain natriuretic peptide was found in all 5 regions of human brain examined (cerebral cortex, thalamus, cerebellum, pons and hypothalamus) (0.6-6.7 pmol/g wet weight, n = 3). These values were comparable to the concentrations of immunoreactive alpha atrial natriuretic peptide in human brain (0.5-10.1 pmol/g wet weight). However, Sephadex G-50 column chromatography showed that the immunoreactive human brain natriuretic peptide in the human brain eluted earlier than synthetic human brain natriuretic peptide-32. These findings suggest that human brain natriuretic peptide is present in the human brain mainly as larger molecular weight forms.


Asunto(s)
Química Encefálica , Proteínas del Tejido Nervioso/análisis , Anciano , Factor Natriurético Atrial/inmunología , Autopsia , Reacciones Cruzadas , Femenino , Humanos , Masculino , Péptido Natriurético Encefálico , Proteínas del Tejido Nervioso/inmunología , Radioinmunoensayo/métodos , Sensibilidad y Especificidad , Especificidad de la Especie
17.
Peptides ; 15(2): 287-90, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-8008633

RESUMEN

C-type natriuretic peptide (CNP) in human adrenal glands and adrenal tumors was measured with a specific radioimmunoassay for CNP. Tissue immunoreactive (IR-) CNP concentrations were 0.54 +/- 0.40 pmol/g wet tissue (gwt) (mean +/- SD) in 14 pheochromocytomas, 0.69 +/- 0.19 pmol/gwt in six adrenocortical tumors, and 0.49 +/- 0.22 pmol/gwt in seven normal adrenal glands (cortex and medulla mixed). These concentrations were comparable to those found in tissues from human brains. Sephadex G-50 superfine column chromatography and reverse-phase high performance liquid chromatography revealed that IR-CNP in normal adrenal glands and pheochromocytoma consisted of at least two components: a component in low molecular weight form chromatographically identical to CNP-22 and the other, a high molecular weight form very similar to human CNP-53. This study has shown that IR-CNP is present in human adrenal glands and adrenal tumors with similar molecular forms and comparable concentrations to those in the human brain.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/química , Glándulas Suprarrenales/química , Factor Natriurético Atrial/aislamiento & purificación , Proteínas del Tejido Nervioso/aislamiento & purificación , Adenoma/química , Adenoma/inmunología , Neoplasias de las Glándulas Suprarrenales/inmunología , Anciano , Factor Natriurético Atrial/inmunología , Cromatografía en Gel , Cromatografía Líquida de Alta Presión , Femenino , Humanos , Masculino , Persona de Mediana Edad , Péptido Natriurético Tipo-C , Proteínas del Tejido Nervioso/inmunología , Feocromocitoma/química , Feocromocitoma/inmunología , Radioinmunoensayo
18.
Peptides ; 14(3): 643-6, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8332560

RESUMEN

The presence of human melanin-concentrating hormone (MCH) was studied in the human brain by radioimmunoassay and immunocytochemistry. Immunoreactive MCH concentrations in the human brain ranged from 0.07 to 19.7 pmol/g wet weight. High performance liquid chromatography of the hypothalamus showed a large immunoreactive peak in the position of human/rat MCH, which was eluted 9 min later than that of salmon MCH. Free-floating sections (40 microns) of the hypothalamus were immunostained. Positive MCH immunostaining was found in perifornical, tuberomammillary, and posterior nuclei. Numerous MCH-immunoreactive nerve fibers were observed throughout the hypothalamus. The presence of high concentrations of MCH in the human brain, in particular in the hypothalamus, suggests that MCH is a neurotransmitter, a neuromodulator, or a neurohormone in man.


Asunto(s)
Química Encefálica , Hormonas Hipotalámicas , Melaninas/análisis , Hormonas Hipofisarias/análisis , Anciano , Cromatografía Líquida de Alta Presión , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Radioinmunoensayo
19.
Peptides ; 10(1): 201-4, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2787502

RESUMEN

Calcitonin gene-related peptide (CGRP) is reported to exist in high concentrations in plasma and tumor tissues of medullary thyroid carcinomas. CGRP-like immunoreactivity (LI) in tumor tissues of pheochromocytomas was investigated by radioimmunoassay. CGRP-LI in 9 pheochromocytomas ranged from 0.50 to 1240 ng/g wet tissue. Sephadex G-50 column chromatography revealed that most of CGRP-LI in tumor extracts was eluted in an identical position to synthetic human CGRP. Reverse-phase high pressure liquid chromatography revealed that CGRP-LI in tumor extracts was eluted in an identical position to synthetic human CGRP and in a more hydrophobic position. These results indicate that high concentrations of CGRP-LI also exist in tumor tissues of pheochromocytomas.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/análisis , Calcitonina/análisis , Neuropéptidos/análisis , Feocromocitoma/análisis , Péptido Relacionado con Gen de Calcitonina , Cromatografía en Gel , Humanos , Neuropéptidos/inmunología , Neuropéptidos/aislamiento & purificación , Radioinmunoensayo
20.
Regul Pept ; 49(1): 19-24, 1993 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-8278630

RESUMEN

Pituitary adenylate cyclase activating polypeptide (PACAP) is a 38 amino acid peptide originally isolated from ovine hypothalamus. It has a potent stimulatory action on adenylate cyclase in the rat pituitary. The presence of PACAP was studied in the tumor tissues of ganglioneuroblastoma and neuroblastoma by radioimmunoassay and immunocytochemistry. Immunocytochemical studies showed positive immunostaining in 4 out of 7 ganglioneuroblastomas and 4 out of 6 neuroblastomas. Immunoreactive PACAP concentrations in tissues of 3 ganglioneuroblastomas ranged from 14.5 to 27.8 pmol/g wet weight (20.0 +/- 5.7 pmol/g wet weight, mean +/- S.D.) and the concentration in one neuroblastoma tissue was 111.0 pmol/g wet weight. Reverse phase high performance liquid chromatography of the tumor tissue extract of ganglioneuroblastoma showed a peak eluting in the position of PACAP1-38 and smaller broad peaks eluting later. These results indicated that high concentrations of immunoreactive PACAP were present in the tumor tissues of ganglioneuroblastoma and neuroblastoma, and suggest the possibility that this peptide plays a pathophysiological role in some ganglioneuroblastomas and neuroblastomas.


Asunto(s)
Ganglioneuroblastoma/química , Neuroblastoma/química , Neuropéptidos/análisis , Niño , Preescolar , Cromatografía en Gel , Cromatografía Líquida de Alta Presión , Femenino , Humanos , Inmunohistoquímica , Lactante , Masculino , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa , Radioinmunoensayo
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