Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Peptides regulate neuroendocrine and limbic system functioning in animals. Both systems show major disturbances in the affective disorders. Only thyrotropin releasing hormone (TRH), luteinizing hormone releasing hormone (LHRH), melanocyte stimulating hormone inhibiting factor (MIF-I), and 1-desamino-8-D-arginine vasopressin (DDAVP) have been administered to affectively ill patients. The thyroid stimulating hormone (TSH) response to TRH is blunted (less than or equal to 5 microU/ml) in some patients during depression and mania and in alcoholics. The blunted response may be an important tool in the diagnosis of depression and mania. Together with other demonstrated endocrine abnormalities, the blunted TSH response suggests a profound alteration in the physiological relationship between the central nervous system and the anterior pituitary in affective illness. Behaviorally, TRH, LHRH, DDAVP, and MIF-I have general activating effects in human that have not yet been demonstrated to be restricted to or specific to affective illness. The interpretation of peptide challenges, however, in the study of affective illness is obfuscated by the small number of patients used and the multiple sites that peptides at pharmacological doses may affect.
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PMID:Peptide challenges in affective illness. 611 86

Seven patients with persistent hyponatremia but normal or elevated serum arginine vasopressin levels and refractory ascites undergoing peritoneovenous shunting were studied in a Metabolic Unit on a 20 mEq sodium 1200 ml fluid-restricted diet to elucidate the mechanism of this response. The intravascular volume expansion after shunt implantation resulted in improvements in cardiac output, renal plasma flow and creatinine clearance (70.7 +/- 9.5 to 140.1 +/- 18.5 ml/min, p less than 0.005). There was an immediate diuresis (632 +/- 135 to 2450 +/- 323 ml/day, p less than 0.005) and natriuresis (3 +/- 1 to 25.9 +/- 10.6 mEq/24 h, p less than 0.05), and urine osmolality decreased significantly (622 +/- 91 to 251 +/- 76 mosmol/L, p less than 0.05) with a significant rise in serum sodium concentration by 72 hr (131 +/- 2 to 135 +/- 1.6 mEq/L, p less than 0.05) and serum osmolality. Serum arginine vasopressin levels remained elevated at 3.85 +/- 0.94 microU/ml, however, although a transient depression cannot be excluded. Subsequently, a small but significant decrease in serum arginine vasopressin levels to 3.04 +/- 0.65 microU/ml (p less than 0.05) was associated with a further rise in serum sodium levels above baseline values (138 +/- 1.4 mEq/L, p less than 0.01) and in serum osmolality. In conclusion, these results indicate that in this group of cirrhotic patients with refractory ascites, intrarenal factors, such as decreased delivery of filtrate to the distal nephron as well as elevated inappropriate levels of arginine vasopressin, are important in the pathogenesis of hyponatremia.
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PMID:Hyponatremia and arginine vasopressin secretion in patients with refractory hepatic ascites undergoing peritoneovenous shunting. 633 10

Responses to intravenous injections of an endotoxin (E. coli-lipopolysaccharide, 1 microgram/kg b.wt.) and endogenous pyrogen were studied in euhydrated and hyperhydrated goats. The biphasic febrile response to the endotoxin was associated with a pronounced increase in the renal excretion of measured prostaglandin (PG) metabolites (11-ketotetranor PGF metabolites). This increase was time-correlated with the elevation of the rectal temperature, and (in hyperhydrated animals) with an inhibition of the water diuresis and an increase in renal excretion of arginine vasopressin (AVP). Other effects of the endotoxin were an immediate depression of renal Na and K excretion followed by the development of pronounced natriuresis, and a reduction of plasma Fe and Zn concentrations. The appearance of the febrile reactions (peripheral vasoconstriction and shivering) was accompanied by miosis. The maximum elevation of the rectal temperature was significantly greater during euhydration than during hyperhydration. Also endogenous pyrogen elicited miosis concomitant with febrile reactions, and an elevation of the renal excretion of PG metabolites which was closely correlated in time with the monophasic febrile response, and (during hyperhydration) with temporary inhibition of the water diuresis and an increase in the renal AVP excretion. However, the responses were much weaker than the corresponding endotoxin effects. No appreciable changes in renal excretion of Na and K were observed in response to the endogenous pyrogen. It is concluded that the observed effects on renal cation excretion were manifestations of direct endotoxin influences on kidney function.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Renal excretion of prostaglandin metabolites, arginine vasopressin, and sodium during endotoxin and endogenous pyrogen induced fever in the goat. 638 26

The activity of antidromically identified supraoptic neurosecretory neurones was recorded in Sprague-Dawley rats under urethane or sodium pentobarbitone anaesthesia during cooling of the body with a cold pack. Of twelve phasic neurones studied during a complete cooling and rewarming cycle, six displayed an initial increase, followed by a depression in activity during the period of reduced body temperature. The remaining six phasic neurones did not alter their activity during cooling. Non-phasic neurohypophysial neurones displayed a reversible reduction (n = 8), or increase (n = 6) in activity during cooling, while seven neurones were unaffected by changes in body temperature. In four other anaesthetized Sprague-Dawley rats, urine flow was reduced by approximately 50% during cooling; this was followed by a diuresis after removal of the cold pack and return of body temperature to normal. The antidiuresis did not occur in homozygous Brattleboro rats which lack arginine vasopressin. The electrophysiological data from a proportion of the supraoptic neurohypophysial neurones correlate with the observed changes in urine flow.
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PMID:Effect of cooling on supraoptic neurohypophysial neuronal activity and on urine flow in the rat. 674 84

To assess the ability of the liver to remove immunoreactive arginine vasopressin (AVP) from the circulation and to determine the effect of certain metabolic factors on the process, a study was carried out with rat livers perfused at 37 C with an oxygenated albumin--electrolyte solution containing AVP (117 +/- 4.5 muU/ml). In controls, the hepatic clearance of AVP was 795 +/- 120 microliter/min (SEM). The addition of AVP in concentrations up to 9029 microU/ml, perfusion with a glucose-free medium, or perfusion without oxygen did not significantly alter the hepatic clearance of AVP. However, perfusion with cold medium (11 C) significantly altered AVP removal in that initially AVP removal increased, while later on AVP removal became completely inhibited. This phenomenon may possibly be a consequence of a cold-induced increase in hepatic AVP trapping which is rapidly saturated due to a cold-induced depression of AVP transport and degradation. Support for this thesis was provided by finding that high AVP concentrations depressed the cold-endhancing removal phase.
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PMID:Removal of immunoreactive arginine vasopressin by the perfused rat liver. 735 52

The effect of thiopentone/halothane anaesthesia on the release of endogenous opioid, adrenocorticotrophin, arginine vasopressin, cortisol and catecholamine was investigated in ponies. The contribution made by halothane itself was studied by maintaining six ponies with a constant 1.2 per cent end tidal halothane concentration and five with a concentration ranging between 0.8 and 1.2 per cent. Cardiorespiratory depression was more prolonged in the ponies receiving a constant 1.2 per cent end tidal halothane concentration than in those which received less halothane. Plasma lactate concentration increased and haematocrit decreased during halothane anaesthesia. The concentrations of met-enkephalin, dynorphin and catecholamines did not change and those of beta-endorphin, adrenocorticotrophin, arginine vasopressin and cortisol increased during halothane anaesthesia. Halothane appeared to be a major stimulus to pituitary adrenocortical activation because the adrenocortical secretion was proportional to the amount of halothane inhaled. Beta-endorphin increased proportionally more than adrenocorticotrophin and their plasma concentrations were not correlated, suggesting that they have independent secretion mechanisms.
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PMID:Pituitary-adrenal activity and opioid release in ponies during thiopentone/halothane anaesthesia. 770 57

Potassium-induced cortical spreading depression (CSD) on prostaglandin E1 (PGE1) induced fever has been investigated in a dose-responsive experimental design in both conscious and urethane-anesthetized adult male Sprague-Dawley rats. While CSD in itself had no effect on nonfebrile body temperature even under cold ambient conditions, CSD significantly suppressed small but not large fevers induced by intracerebroventricular PGE1. The increased oxygen consumption during fever was also reduced. We also explored the possible involvement of the antipyretic peptide arginine vasopressin, in the CSD-induced suppression of fever. Long term castrated rats have significantly reduced ventral septal levels of this peptide, yet CSD was effective in suppressing the initial 40 min of PGE1 fever in these animals. Thus we conclude that increased release of ventral septal arginine vasopressin is probably not involved in the action of CSD on fever.
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PMID:Effect of potassium-induced cortical spreading depression on prostaglandin-induced fever in conscious and urethane-anesthetized rats. 782 79

1. The aim of this study was to compare antianginal effects of (+/-)-(E)-ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexeneamide (FK409), a new spontaneous nitric oxide releaser, with those of isosorbide dinitrate (ISDN). We used two types of rat angina model; methacholine- and arginine vasopressin (AVP)-induced coronary vasospasm models. 2. In the in vitro study, FK409 showed 80 times more potent vasorelaxant effect in dog isolated coronary artery than ISDN (EC50 = 16.7 +/- 4.8 and 1340 +/- 320 nM, respectively). 3. In the rat methacholine-induced coronary vasospasm model, FK409 suppressed the elevation of ST segment dose-dependently and significantly at 0.1 mg kg-1, i.d. On the other hand, ISDN suppressed it significantly at 3.2 mg kg-1, i.d. In addition, the efficacy of 3.2 mg kg-1 ISDN in the model was almost the same as that of 0.1 mg kg-1 FK409. 4. In the above experiments, FK409 and ISDN decreased mean blood pressure significantly at the maximum dose tested (1.0 mg kg-1, i.d. and 3.2 mg kg-1, i.d., respectively) but did not change heart rate at these doses. Therefore, the hypotensive effect of FK409 was 10 times weaker than the antianginal effect of the compound, while those of ISDN were almost the same. 5. In the rat AVP-induced coronary vasospasm model, 32 mg kg-1 FK409 significantly inhibited the depression of ST segment 60 min after oral administration. On the other hand, 32 mg kg-1 ISDN did not inhibit it at 60 and 120 min after oral administration. 6. In conclusion, FK409 inhibits coronary vasospasm more potently in two types of rat angina models than ISDN. In addition, FK409 shows an antianginal effect more selectively that a hypotensive effect,compared with ISDN.
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PMID:Antianginal effects of FK409, a new spontaneous NO releaser. 788 66

In rabbit cortical collecting duct (CCD) cells, arginine vasopressin (AVP) causes a transient increase followed by a sustained depression of transepithelial potential difference (PDte). Mechanisms underlying the decrease in PDte are not well understood. In this study, we used primary cultures of rabbit CCD cells to study effects of AVP. Basolateral addition of AVP caused a dose-dependent increase in transepithelial conductance (Gte) and a corresponding decrease in PDte. A significant effect was observed at 1 pM AVP, and half-maximal response occurred at 30 pM AVP; 1 nM AVP increased Gte and decreased PDte. Replacement of apical Na+ with N-methyl-D-glucamine did not prevent the effect of AVP on Gte, suggesting that it is not mediated by an increase in apical Na+ conductance. Similarly, apical Ba2+ (1 mM) or 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS, 0.1 mM) failed to prevent the effect of AVP. On the other hand, 5-nitro-2(3-phenylpropylamino)benzoic acid (0.1 mM) caused partial inhibition, whereas substitution of apical Cl- with gluconate or cyclamate almost completely prevented the AVP-induced increase in Gte. In unidirectional ion-flux studies, 1 nM AVP caused only a modest increase in apical-to-basolateral (A-->BL) flux of 22Na and had no effect on transepithelial flux of 86Rb in either direction. On the other hand, AVP caused a pronounced increase in A-->BL flux and BL-->A flux of 36Cl, resulting in an increased net Cl- absorption. The effect of AVP on Gte could be mimicked by 8-bromo-adenosine 3',5'-cyclic monophosphate (8-bromo-cAMP) and isoproterenol, and effects of AVP and isoproterenol were not additive.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Vasopressin activates a chloride conductance in cultured cortical collecting duct cells. 797 87

Prolyl endopeptidase (PEP) is a serine proteinase, which may cleave peptides that are involved in the pathophysiology of major depression, such as arginine vasopressin, beta-endorphin, luteinizing hormone-releasing hormone, thyrotropin-releasing hormone, and maybe corticotropin-releasing hormone. PEP may be involved in activation of cell-mediated immunity, autoimmune and inflammatory responses, which repeatedly occur in severe depression. The present study investigates serum PEP activity in 33 normal controls, 16 minor, 14 simple major, and 18 melancholic depressed subjects. Pre-dexamethasone and post-dexamethasone (DST) intact adrenocorticotropic hormone (ACTH) and cortisol values were determined in 33 depressed subjects. Serum PEP activity was significantly lower in depressed subjects compared to normal controls and in melancholic depressed subjects compared to minor and simple major depressed subjects. Up to 61.1% of the melancholic patients had serum PEP activities below the mean PEP values of normal controls minus two SDs. In the depressed study group, significant negative correlations between serum PEP activity and severity of illness, post-DST cortisol, and ACTH values were observed. There was a trend toward higher serum PEP activity with increasing age. It is hypothesized that lower serum PEP activity, and lower serum activity of other peptidases, may play a role in the neuroendocrine and immune pathophysiology of major depression.
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PMID:Lower serum prolyl endopeptidase enzyme activity in major depression: further evidence that peptidases play a role in the pathophysiology of depression. 803 98


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