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)

Animal studies have revealed two important aspects of vasopressin function which make this peptide a suitable candidate for involvement in complex behavioural syndromes: (1) vasopressin deficiency produces deficits of behaviour which are reversed by vasopressin; (2) well-developed systems exist for the distribution of vasopressin throughout the central nervous system (C.N.S.) via either peptidergic neurons or the cerebrospinal fluid (C.S.F.) and provide the means by which vasopressin may regulate cells controlling behavioural or physiological processes. Among the processes which vasopressin can influence are several of significance in the symptom-complex of affective illness, including alterations in memory, changes in pain sensitivity, synchronisation of biological rhythms, the timing and quality of R.E.M. sleep, and the regulation of fluid and electrolyte balance. In addition, vasopressin is functionally linked to monoamine neurotransmitter systems and, like them, is altered by pharmacological agents which affect mood. Some of the pharmacological and clinical data suggest that vasopressin function is diminished in depression and augmented in mania; sometimes, however, alterations in vasopressin function may be detectable only during crucial periods of the manic-depressive cycle. The hypothesis that vasopressin plays a role in disorders of human behaviour, particularly manic-depressive illness, can now be directly tested by radioimmunoassays of vasopressin in C.S.F. and plasma and by the administration of specific vasopressin analogues and inhibitors.
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PMID:Vasopressin in affective illness. 7 97

Lithium intoxication was induced in rats by intraperitoneal administration of lithium chloride in a daily dose of 200 mg/kg (0.22 LD50) for 6 days. Polyuria connected with pathological changes in the epithelium of the convoluted tubules and depression of the antidiuretic hormone--acid mucopolysaccharides system in the area of the straight kidney tubules was observed on the 6th day of the experiments. Oligouria and death of some of the animals on the 7th experimental day was caused by severe lesions the kidney structure. Further observation (30 days) demonstrated that, along with the regeneration processes, there developed a marked sclerosing ofthe kidney tissue. A conclusion was drawn that severe lithium intoxication was associated with the development of acute renal insufficiency. Functional reserves of the kidneys after the cessation of lithium chloride administration remained lowered for a long period.
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PMID:[Role of the kidneys in the pathogenesis of lithium poisoning]. 13 80

Using micropuncture techniques, the author studied the effect of vasopressin on renal function in young rats at three stages of development -- in the middle of the weaning period (22 days), after weaning was over (30 days) and at the beginning of the sexual maturation period (42 days). In the presence of a hypotonic load, a small dose of vasopressin (12 muU/100 g b.w., i.v.) was most effective in the youngest age group, where it reduced the urine flow by 82% both by increasing water reabsorption and by reducing the GFR. In this group, vasopressin lowered the TF/P Na+ ratio and raised the TF/P K+ ratio in the initial part of the distal tubules of the superficial nephrons, but raised water absorption only beyond the initial part of the distal tubules. Vasopressin reduced the urine flow by 72% in 30-day-old rats by raising water reabsorption beyond the initial part of the distal tubules. The only ion to be affected was K+, whose concentration rose in the final urine. In 42-day-old rats the effect of vasopressin was manifested in only mild depression of the GFR. In this age group, as distinct from younger animals, anaesthesia and surgery evidently led to endogenous vasopressin release, so that the small dose of exogenous vasopressin did not significantly influence the test parameters. This is also underlined by the significant difference between the control urine flow of the 42-day-old and the younger rats.
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PMID:The effect of vasopressin on renal function in young rats a clearance and micropuncture study. 13 28

Lithium (Li+) chloride, 2 to 3 mEq. per kilogram of body weight, was administered intraperitoneally to normal Wistar rats daily for 4 to 66 days. This resulted in a marked reduction in urine osmolality (Uosm.) and increase in the excretion of water, Na+, K+, uric acid, and phosphate. The excretion of uric acid and potassium was a direct function of UNaV. The magnitude of depression in urine osmolality was significantly related to the rate of excretion of lithium in the urine, suggesting that the change in water reabsorption is dependent on the presence of the ion in the luminal side of the tubule. During 2 per cent saline diuresis, Li+-treated rats achieved less fractional free water reabsorption (TcH2O/GFR times 100) at any level of fractional osmolar clearance (Cosm./GFR times 100) than normal rats. On the other hand, during 0.225 per cent saline diuresis, fractional free water clearance (CH2O/GFR times 100) was normal over a wide range of fractional urine flow (V/GFR times 100), indicating intact function of the ascending limb of the loop of Henle. The intravenous infusion of vasopressin (VP) or dibutyryl cyclic-adenosine monophosphate (dcAMP) to Li+-treated rats resulted in a modest rise in Uosm. and a reduction in V/GFR times 100 and CH2O/GFR times 100. Although the response to VP appeared earlier than that to dibutyryl cyclic-AMP, the magnitude of the changes in Uosm., V/GFR times 100, and CH2O/GFR times 100 was eventually the same with both substances. Comparison between normal and Li+-treated rats revealed that the response to both VP and dibutyryl cyclic-AMP was blunted, albeit to a greater extent in the former. Inhibition by Li+ of adenylate cyclase will only partially explain the present data. Impairment in the release of endogenous VP or a block distal to the formation of cyclic-AMP must have played a role. In view of a normal diluting capacity and the increase in the excretion of phosphate and uric acid, it is suggested that Li+, when administered chronically in the present doses, inhibits proximal tubular reabsorption.
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PMID:Renal effects of lithium administration in rats: alterations in water and electrolyte metabolism and the response to vasopressin and cyclic-adenosine monophosphate during prolonged administration. 16 79

Vasopressin increases the permeability of the total urinary bladder, an analogue of the mammalian renal collecting duct, to water and small solutes, especially the amide urea. We have observed that three general anesthetic agents of clinical importance, the gases methoxyflurane and halothane and the ultrashortacting barbiturate methohexital, reversibly inhibit vasopressin-stimulated water flow, but do not depress permeability to urea, or the the lipophilic solute diphenylhydantoin. In contrast to their effects in vasopressin-treated bladders, the anesthetics do not inhibit cyclic AMP-stimulated water flow, consistent with an effect on vasopressin-responsive adenylate cyclase. The selectivity of the anesthetic-induced depression of water flow suggests that separate adenylate cyclases and cyclic AMP pools may exist for control of water and urea permeabilities in to toad bladder. Furthermore, theophylline's usual stimulatory effect on water flow, but not its effect on urea permeability, was entirely abolished in methoxyflurane-treated bladders, suggesting that separate phosphodiesterases that control water and urea permeabilities are present as well. We conclude that the majority of water and urea transport takes place via separate pathways across the rate-limiting luminal membrane of the bladder cell, and that separate vasopressin-responsive cellular pools of cyclic AMP appear to control permeability to water and to urea.
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PMID:Selective inhibition of osmotic water flow by general anesthetics to toad urinary bladder. 18 13

The authors studied the dynamics of natural substrates of neurohumoral origin (oxytocin and lysine-vasopressin) by the serum of pregnant and nonpregnant women in relation to the pH in the medium, within pH limits of 2.5 to 8. The values obtained in a polarographic study of depression of the complex oxytocin and lysine-vasopressin polarographic wave by pregnancy and non-pregnancy sera and the results of a parallel analysis of free amino acids of the inactivated substrates under the same conditions showed that, apart from deep degradation of the studied substrates at the optimum pH (5.5 minus 8), less pronounced degradation of the molecule at low pH values (3 minus 4,5), i.e. in a non-physiological blood medium, also occurred. On the basis of their results, the authors submit the hypothesis of the existence of oxytocinase isoenzymes and of the probable presence of several peptidases with overlapping specificity.
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PMID:The influence of pH in the medium on degradation of neurohormones by pregnancy serum. 23 51

The renal response to left atrial balloon inflation in normal dogs was compared with that in dogs with chronic congestive heart failure (CHF). CHF was induced by the production of an aortocaval fistula below the level of the renal arteries. CHF dogs showed elevated left ventricular end-diastolic pressure, enlarged hearts, a depression of myocardial contractility, pulmonary edema, ascites, and peripheral edema. They also showed significant decreases in urine flow, creatinine clearance, para-aminohippurate clearance, sodium and potassium excretion, fractional sodium excretion, osmolar clearance, arterial blood pressure, and heart rate. Balloon distension of the left atrium evoked a significant increase in urine flow and free-water clearance in the normal group. The reflex nature of this response was indicated by its blockade after bilateral cervical vagotomy. In contrast, the CHF group did not exhibit significant changes in urine flow or free-water clearance during balloon inflation. Plasma antidiuretic hormone (ADH) was significantly elevated in the CHF group; however, balloon distension reduced plasma ADH in both groups of dogs. Plasma renin activity was significantly elevated in the CHF dogs and was not changed by balloon distension in either group of dogs. It is concluded that animals with high-output CHF do not exhibit the atrial-diuretic reflex in spite of their ability to reduce ADH levels by atrial distension.
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PMID:Renal effects of left atrial distension in dogs with chronic congestive heart failure. 43 20

The effects of several types of vasopressin analogs that are considered to be resistant to some of the physiologically significant enzymatic systems were investigated utilizing rats trained in a passive avoidance task. Enhancement of avoidance latencies was observed 2, 7 and 13 days after the single learning trial when deamino-carbavasopressins, triglycyl-8-lysine-vasopressin or its des-glycinamide derivative, and deamino-D-arginine-vasopressin were given shortly after the learning trial in the dose of 1 microgram s.c. (8-L-Arginine)deamino-6-carba-vasopressin and (8-L-ornithine)deamino-6-carba-vasopressin were also active in the dose of 0.1 microgram. Lysine vasopressin and its des-glycinamide derivative failed to enhance avoidance latencies in part of the experiments if doses of 0.3--3 micrograms were administered and 7 or 13 day intervals were used between the learning and the test trials. Enhancement of avoidance latencies was also observed, if some of the peptides were injected 20 min but not 120 or 180 min before the test trial. Marked depression of exploratory behavior of rats in an open field was found after s.c. injections of low doses (1--3 micrograms kg-1) of deamino-carba-vasopressins. Higher doses (10--30 micrograms kg-1) induced sleep-like immobility not accompanied by ataxia or catalepsy.
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PMID:Vasopressin analogs: sedative properties and passive avoidance behavior in rats. 47 29

Hyponatremia with simultaneous renal sodium loss was associated with the inappropriate secretion of antidiuretic hormone in a dog with heartworm disease. Antidiuresis caused expansion of extracellular fluid volume, which induced renal salt wasting and a negative sodium balance. The combination of water retention, salt wasting, and inactivation of intracellular solute contributes to the decrease in serum sodium concentration. Water intoxication due to hypotonicity of body gluids induced anorexia, depression, weakness, and incoordination.
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PMID:Inappropriate secretion of antidiuretic hormone in a dog. 50 Apr 39

1. The influence of partial hepatectomy on urinary concentrating ability and renal tissue sodium was determined in conscious rats deprived of water for 24 h. In comparison with a sham operation, partial hepatectomy resulted in: a) a 50% reduction in free-water reabsorption, urinary osmolality, and osmolal urine-to-plasma ratio; b) depression of free-water reabsorption at similar levels of osmolal clearance above 200 microliter/min per ml of GFR during the infusion of hypertonic NaCl and vasopressin; and c) a 30% reduction in sodium content of the renal papilla and outer medulla. 2. The renal response to an intravenous water load (2.5% glucose infused to 2.5% of body wt at 0.4 ml/min) was determined in sham-operated and partially hepatectomized, conscious rats. By 60 min after the water load, both groups had excreted practically all of the load. However, during and for 30 min after the infusion in the partially hepatectomized group, the percent of the water load excreted, urine flow, and free-water clearance were significantly reduced while urinary osmolality and osmolal urine-to-plasma ratio were significantly elevated. 3. These experiments demonstrate that shortly after partial removal of the liver the renal concentrating ability is defective and the excretion of a water load is not grossly impaired.
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PMID:Concentration and dilution of the urine in partially hepatectomized, conscious rats. 56 70


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