Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01185 (vasopressin)
 23,126 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study has examined the effects of insulin-induced hypoglycemia on expression of the CRH, arginine vasopressin, and POMC genes and corresponding peptides in freely moving, unanesthetized, male Sprague-Dawley rats. Animals were infused with 150 mM NaCl for 3 days before the experimental day and were then administered insulin (4 U/kg) or saline iv. In one experiment animals were killed 0, 30, 60, or 90 min after insulin or saline, and RNA was isolated from anterior pituitary, cerebral cortex, and punches of the hypothalamic paraventricular and supraoptic nuclei. In a second experiment, animals were killed 90 min after insulin or saline treatment, and RNA was isolated from whole hypothalami. RNA was analyzed by Northern blot. Plasma glucose fell from 106 +/- 5 to 38 +/- 2 mg/dl after insulin administration and remained low for the duration of the experiment. Plasma levels of ACTH, corticosterone, and vasopressin were 10-, 6-, and 4-fold higher, respectively, in the insulin-treated vs. control animals (by analysis of variance, P less than 0.0001 in all cases), while plasma CRH was unchanged. During hypoglycemia POMC mRNA levels were 1.8-fold higher in the insulin-treated group (by analysis of variance, P less than 0.025). In contrast, paraventricular nucleus, whole hypothalamic, and parietal cortex CRH mRNA and vasopressin mRNA were unchanged. These data support previous studies which indicated that POMC gene expression is increased by hypoglycemia. However, we found no evidence for an increase in paraventricular nucleus or cerebral cortex CRH mRNA expression during hypoglycemia-associated stimulation of the hypothalamic-pituitary-adrenal axis, suggesting that another factor(s) may mediate the observed increase in POMC gene expression.
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PMID:The effect of insulin-induced hypoglycemia on gene expression in the hypothalamic-pituitary-adrenal axis of the rat. 131 Feb 84

A 42-year-old man and a 51-year-old woman with a positive history of weakness and gastrointestinal complaints were shown to have low basal plasma cortisol and ACTH levels, and low daily urinary excretion of free cortisol. An empty sella was found in patient no. 1, while patient no. 2 was hypothyroid. Both patients showed a normal plasma cortisol response to ACTH and an increment in plasma ACTH and lipotropin levels after ovine CRH (oCRH), lysine vasopressin (LVP) and oCRH-LVP stimulation tests. These studies clearly report an isolated idiopathic ACTH deficiency due to a deficit in CRH in two adult subjects.
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PMID:Isolated adrenocorticotropic hormone deficiency secondary to hypothalamic deficit of corticotropin releasing hormone. 131 44

Administration of interleukin-1 (IL-1) induces increases in plasma ACTH and glucocorticoids. Numerous experiments have implicated the hypothalamic CRH neurosecretory system in these responses, but have failed to provide evidence for involvement of the ACTH secretagogue vasopressin (VP). The rat CRH neurosecretory system contains two types of cells: VP expressing and VP deficient. Hence, the above findings suggested that IL-1 may selectively activate the VP-deficient subtype of CRH neurosecretory cells. In this study we employed postembedding electron microscopic immunocytochemistry to directly assay IL-1-induced depletion of secretory vesicles from identified VP-expressing and VP-deficient CRH neurosecretory axons. IL-1-induced depletion of secretory vesicles from these axons was correlated with increases in plasma ACTH and decreases in plasma PRL. No dose of IL-1 was found that could selectively activate one subtype of CRH neurosecretory axons; at doses of 0.67 microgram/100 g and above for both IL-1 alpha and IL-1 beta, equal depletion of vesicles from the two subtypes was observed. Similar results were previously found after the injection of bacterial lipopolysaccharide, which induces the release of IL-1 from macrophages. The findings unequivocally establish for the first time that IL-1 activates hypothalamic CRH neurosecretory cells in the absence of surgical stress, anesthesia, disruption of the infundibular area, or administration of toxic drugs. In addition, these data clearly demonstrate that IL-1 induces the release of VP from neurosecretory axons in the portal capillary zone of the external zone of the median eminence. Previous studies have shown that the VP-deficient subtype of CRH neurosecretory axons is not strongly activated by several types of stress; therefore, activation of the system by inflammatory mediators involves mechanisms different from those mediating the stress response.
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PMID:Effects of interleukin-1 on the stress-responsive and -nonresponsive subtypes of corticotropin-releasing hormone neurosecretory axons. 131 22

Experimental evidence indicates that arginine vasopressin (AVP) contributes to the release of ACTH under certain conditions. The present study investigates the role of vasopressin as a secretagogue of ACTH during cigarette smoking or nicotine infusion with additional injection of corticotropin releasing hormone (CRH) and using the specific AVP antagonist d(CH2)5Tyr(Me)-AVP. We first tested the effect of the AVP antagonist (10 micrograms/kg body weight i.v.) on ACTH and cortisol release following cigarette smoking in 15 healthy young male smokers. Smoking led to marked increments in plasma nicotine and to a small rise in plasma ACTH and cortisol. Mean plasma ACTH and cortisol levels were at no time significantly altered by the antagonist. This might be due to a slight agonistic effect of the AVP antagonist, to high interindividual variability of the ACTH and cortisol responses after smoking or to a negligible role of AVP in smoking-induced ACTH release. In a second study we performed the following tests in six healthy male non-smokers: (1) nicotine infusion (1.0 micrograms/kg body weight per min); (2) CRH i.v. (100 micrograms); (3) AVP antagonist i.v. (5 micrograms/kg); (4) nicotine infusion plus CRH i.v.; (5) nicotine infusion plus AVP antagonist i.v.; (6) nicotine infusion plus CRH and AVP antagonist i.v.; and (7) sham infusion. Nicotine infusion led to greater increments of AVP, ACTH and cortisol than smoking without causing nausea. Peak nicotine levels after nicotine infusion were lower than after smoking. The AVP antagonist in the reduced dosage given alone had no effect on hormone levels. However, it slightly attenuated the effect of nicotine on ACTH and cortisol (P less than 0.05, ANOVA).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The role of vasopressin in the nicotine-induced stimulation of ACTH and cortisol in men. 132 53

Up to now, the diagnosis of silent corticotroph cell pituitary adenomas has been made only on histopathological basis. In this paper we describe 6 women affected with pituitary adenomas, without evident clinical features of hypercortisolism, in whom retrospective data suggested the possibility of clinically diagnosing silent corticotropinomas in vivo. In all patients basal ACTH and cortisol levels were normal, and the low-dose dexamethasone test constantly suppressed serum cortisol and urinary 17-hydroxycorticosteroid levels. The CRH and/or lysine-vasopressin tests, performed in five patients, always induced exaggerated ACTH/cortisol rises. In three cases the response to the opiate agonist loperamide was assessed and no inhibition of ACTH/cortisol levels was found. All patients underwent pituitary surgery. In five cases evidence of corticotropinoma was obtained by immunohistochemistry or immunofluorescence studies; moreover, in one adenoma ACTH was secreted into the culture medium, and in another one CRH and arginine-vasopressin induced a marked intracellular [Ca++] rise. Electron microscopy study of the adenoma, removed from three patients, showed the presence of adenomatous corticotroph cells. Finally, in another woman no hormonal abnormalities were initially observed and she was operated for a "nonfunctioning" pituitary adenoma, but four years later an overt Cushing's disease appeared, suggesting that a silent corticotropinoma subsequently became functional, although the formation of a different adenoma cannot be excluded. In conclusion, the occurrence of ACTH/cortisol hyperresponsiveness to CRH and/or lysine-vasopressin and the lack of suppression of ACTH/cortisol secretion to opioid agonists in patients with apparently "nonfunctioning" pituitary tumors might allow the in vivo recognition of silent corticotropinomas.
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PMID:The silent corticotropinoma: is clinical diagnosis possible? 132 50

In light of prior data that the central administration of vasopressin in animals is associated with abnormal persistence of behaviors acquired under aversive conditioning, we studied the secretion of arginine vasopressin into the cerebrospinal fluid and plasma in patients with obsessive-compulsive disorder and controls. Patients with obsessive-compulsive disorder had significantly elevated basal levels of arginine vasopressin in the cerebrospinal fluid and significantly increased secretion of arginine vasopressin into the plasma in response to hypertonic saline administration. Moreover, seven of 12 patients with obsessive-compulsive disorder showed a loss of the normal linear relationship between plasma arginine vasopressin level and osmolality. In addition, cerebrospinal fluid corticotropin releasing hormone, which has synergistic effects with arginine vasopressin centrally and at the pituitary gland, was also significantly elevated in patients with obsessive-compulsive disorder compared with controls.
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PMID:Abnormalities in the regulation of vasopressin and corticotropin releasing factor secretion in obsessive-compulsive disorder. 137 Jan 98

The effects of emotional stress (ES) corresponding to conditioned fear on colonic motility and its antagonism by [deamino-Pen1, Val4, D-Arg8]vasopressin, a vasopressin antagonist, were investigated by electromyography in conscious fasted rats fitted with chronically implanted electrodes. A 117% increase (19.6 +/- 2.1 vs. 9.0 +/- 0.9 cycles/10 min during the control period) in the frequency of colonic spike bursts was observed when rats were placed for 30 min in a box in which they had previously received electric foot shocks. Intracerebroventricular (icv) administration of corticotropin-releasing hormone (CRH; 0.5 micrograms/kg) mimicked the effects of ES and increased the spike burst frequency of the colon by 88.6% from 5 to 15 min after its administration. At doses between 5 and 20 micrograms/kg the antagonist [deamino-Pen1, Val4, D-Arg8]vasopressin significantly reduced or abolished the effects of ES and CRH administration on colonic motility. Injected icv at doses of 2.5 and 5 ng/kg [Arg8]vasopressin dose dependently increased the frequency of colonic spike bursts. These effects were not reproduced by similar or higher (50 ng/kg) doses given intraperitoneally, and the effects were abolished after previous administration of vasopressin at a dose of 20 micrograms/kg. It is concluded that the effects of ES on colonic motility in rats previously shown to be linked to the central nervous system (CNS) release of CRH are in turn mediated through the central release of vasopressin.
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PMID:CNS vasopressin mediates emotional stress and CRH-induced colonic motor alterations in rats. 155 Feb 33

Antigen-activated immune cells acutely release cytokines which, besides their effects on the immune system, increase hypothalamopituitary-adrenocortical (HPA) function to counteract the inflammatory process. The present study was designed to test, using in vitro paradigms, whether there exists a hypothalamic and/or a median eminence site of action, whereby different substances derived from the immune system could stimulate the CRH and/or the arginine-vasopressin (AVP) neuronal pathway. For this purpose, whole medial basal hypothalamus (containing the median eminence) were dissected from female rats and incubated in vitro with several concentrations of interleukin-1 (IL-1)beta, interleukin-6 (IL-6), tumor necrosis factor (TNF)-alpha, thymosin fraction 5 (TF5) or bacterial lipopolysaccharide (LPS). After a 40-min incubation period, the amounts of CRH and AVP released into the incubation medium were measured by specific radioimmunoassays (RIAs). Additional experiments were carried out by superfusing isolated rat median eminence fragments with the different test substances; CRH and AVP released into the medium were also measured by RIAs. The results indicated that IL-1 beta (10(-11) to 10(-7) M), IL-6 (0.06 x 10(-10) to 0.4 x 10(-10) M), TNF-alpha (6 x 10(-9) to 6 x 10(-7) M) and TF5 (5-500 micrograms/ml) but not LPS (1-100 ng/ml) significantly enhanced hypothalamic CRH secretion above baseline in a concentration-related fashion. Additionally, superfusion experiments demonstrated that, among all test substances, only IL-6 possesses a direct and dose-dependent CRH-releasing activity at the median eminence level. Conversely, no preparation enhanced basal AVP release in either in vitro design.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Cytokines stimulate the CRH but not the vasopressin neuronal system: evidence for a median eminence site of interleukin-6 action. 164 Oct 72

CRH is secreted by the placenta into the maternal and fetal circulation during pregnancy in humans and non-human primates. ACTH and cortisol responses to exogenous CRH are blunted during pregnancy. In the present study we examined the pituitary-adrenal response to another corticotropin releasing factor, vasopressin. Studies were performed in chronically catheterized female baboons moving freely in their home cages; 13 studies were performed in 4 pregnant animals, and 8 studies were performed in 6 nonpregnant animals. Vasopressin was administered iv in 2 doses (0.3 and 3.0 U), and plasma samples were obtained for CRH, ACTH, and cortisol measurements. Results are expressed as the mean +/- SEM. Baseline plasma CRH was 240 +/- 20 pmol/L in the pregnant animals and unmeasurable (less than 20) in the nonpregnant animals. In the pregnant animals, ACTH concentrations rose from a baseline of 6.4 +/- 1.3 pmol/L to 10.1 +/- 0.4 after 0.3 U vasopressin and to 24.9 +/- 5.2 after 3.0 U vasopressin. In the nonpregnant animals, ACTH levels were 5.8 +/- 1.3 at baseline, 6.7 +/- 1.3 after the 0.3-U dose, and 14.6 +/- 2.4 after the 3.0-U dose. The peak ACTH response after each dose of vasopressin was higher in the pregnant animals than in the nonpregnant animals (P less than 0.05). The baseline cortisol level in the pregnant animals was 960 +/- 80 nmol/L and rose to 1370 +/- 110 and 1535 +/- 165 after the 2 doses of vasopressin, respectively. The baseline cortisol concentration in the nonpregnant animals was 910 +/- 86 nmol/L. The cortisol level was 990 +/- 75 after the 0.3-U vasopressin dose and 1380 +/- 140 after the 3.0-U dose. The peak cortisol response after the 0.3-U dose was significantly higher in the pregnant animals (P less than 0.02), while the peak cortisol responses after the 3.0-U dose were similar in the 2 groups of animals. In a single animal, vasopressin was administered sequentially at 4 gestational ages during pregnancy and then 2 times in the postpartum period. The ACTH response to vasopressin increased as pregnancy progressed and then decreased in the postpartum period. In summary, the ACTH and cortisol responses to 0.3 and 3.0 U vasopressin, iv, are enhanced during pregnancy in the baboon, although the responses to exogenous CRH are blunted during gestation. We conclude that the chronic placental CRH stimulation of the pituitary-adrenal axis during pregnancy leads to an enhanced response to vasopressin and a down-regulation of the response to exogenous CRH.
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PMID:Adrenocorticotropin and cortisol responses to vasopressin during pregnancy. 164 36

To explore the effects of repeated episodes of hypercortisolemia on hypothalamic-pituitary-adrenal axis regulation, we studied plasma ACTH and cortisol (CORT) responses to 100 micrograms human CRH (hCRH) in 10 dexamethasone (1.5 mg)-pretreated elderly endurance athletes who had abstained from physical activity for at least 48 h before testing and 13 sedentary age-matched controls. Basal CORT and ACTH levels were indistinguishable between runners and sedentary controls, whereas CORT responses to hCRH were significantly increased in endurance athletes, and ACTH responses tended to be higher in this group. Comparing the dexamethasone/hCRH test results of the runners with those of an age-matched sample of previously studied depressed patients (n = 9), similar hormone responses to CRH challenge were noted. The mechanisms underlying these alterations may either be a stepwise decrease in corticotropic sensitivity to the negative feedback signal leading to a switch to positive glucocorticoid feedback, an enhanced cosecretion of ACTH secretagogues such as vasopressin, or a combination of both. In conclusion, hypothalamic-pituitary-adrenal axis physiology seems to be determined by previous stressful events associated with hypercortisolemia, regardless of its etiology.
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PMID:Hypothalamic-pituitary-adrenal axis function in elderly endurance athletes. 165 55


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