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)

The role of glucocorticoids and second messenger systems in the regulation of the vasopressin (VP) gene was studied in the human small cell lung carcinoma cell line GLC-8. Small cell lung carcinoma GLC-8 cells express VP mRNA and contain both glucocorticoid and mineralocorticoid receptors. Treatment with the synthetic glucocorticoid dexamethasone when added alone at 10(-8) M had no effect on the VP mRNA level and decreased the level by 30% at 10(-6) M. However, the effect of dexamethasone changed to positive when cells were simultaneously treated with cAMP-enhancing agents. VP mRNA levels, which were elevated by 1.5- to 2-fold by the cAMP-enhancing agents alone, increased a further 1.5- to 3-fold by dexamethasone. Thus, the combined effect of dexamethasone and cAMP stimulation was a 3- to 7.5-fold increase in VP mRNA levels. Long term treatment with the phorbol ester 12-O-tetradecanoyl-phorbol-13-acetate (TPA) reduced the VP mRNA level by 75%. The TPA-suppressed VP mRNA levels could be up-regulated about 6-fold by simultaneous treatment with 8-bromo-cAMP. Dexamethasone did not alter the TPA-suppressed VP mRNA levels. These results indicate that both cAMP and protein kinase-C pathways as well as glucocorticoid receptors are involved in the regulation of VP mRNA levels and that these factors interact. This leads to a negative or positive response of VP gene expression to glucocorticoids in a state-dependent manner. The interactions may be of significance in a physiological context and relate to the different regulation of VP-expressing systems in the brain.
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PMID:Regulation of vasopressin messenger RNA levels in the small cell lung carcinoma cell line GLC-8: interactions between glucocorticoids and second messengers. 171 34

alpha 2-Adrenoceptor subtype expression was investigated in cultured rat inner medullary collecting duct (IMCD) cells using radioligand binding studies, Northern blot analysis, and adenosine 3',5'-cyclic monophosphate (cAMP) assays. [3H]rauwolscine bound to a single class of alpha 2-adrenoceptors with high affinity [Kd = 1.7 +/- 0.3 nM, maximum binding (Bmax) = 45.2 +/- 10.8 fmol/mg protein]. alpha 2-Adrenoceptor ligands inhibited [3H]rauwolscine binding with a rank order of potency characteristic of interaction with the alpha 2B-adrenoceptor [inhibitory constant (Ki) values (in nM) rauwolscine (1.95) greater than ARC-239 (8.52) greater than prazosin (237) greater than oxymetazoline (30,000)]. Northern blot analysis was performed using poly(A)+ RNA isolated from 90% confluent rat IMCD cells and probes derived from alpha 2-adrenoceptor DNA sequences from the rat nonglycosylated alpha 2B-adrenoceptor and the human alpha 2A-adrenoceptor. The alpha 2B probe hybridized to a 4.2-kb band under high stringency conditions, but the alpha 2A-adrenoceptor probe did not hybridize to this band. In functional studies, the full alpha 2-adrenoceptor agonists epinephrine and UK-14,304 potently inhibited vasopressin-stimulated cAMP accumulation by 50 to 70% [half-maximal response (EC50) (in nM) epinephrine = 11.2, UK-14,304 = 6.4]. Guanabenz and clonidine were partial agonists, inhibiting cAMP accumulation by 30 to 40% and were less potent than the full agonists [EC50 (in nM) 56.0 guanabenz and 94.5 clonidine]. Epinephrine-induced inhibition of cAMP accumulation was blocked by rauwolscine, prazosin, and ARC-239 but not by the alpha 1-adrenoceptor antagonist corynanthine. We conclude that rat IMCD cells in primary culture express functional alpha 2-adrenoceptors of the alpha 2B-subtype.
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PMID:Characterization of prazosin-sensitive alpha 2 B-adrenoceptors expressed by cultured rat IMCD cells. 171 24

The renal action of guanabenz, a centrally acting antihypertensive drug, was evaluated in anesthetized New Zealand genetically hypertensive rats and in normotensive Sprague-Dawley rats using clearance techniques. In high doses (1 mg/kg/hr), the drug lowered systemic blood pressure in the hypertensive rats without reducing glomerular filtration rate. Mean urine flow increased from 2.42 +/- 0.34 to 36.52 +/- 4.52 microliters/min per 100 g b.wt. while fractional water excretion increased from 0.34 +/- 0.05 to 4.36 +/- 0.50%. The renal and hemodynamic actions of the drug were sustained throughout the experiment. In a lower dose (10 micrograms/kg/hr), guanabenz reduced blood pressure in the hypertensive rats to an extent similar to that of the higher dose but had only a moderate effect on kidney function. Renal elimination of water, sodium and potassium increased slightly and glomerular filtration rate remained unchanged. Infusion of the vehicle alone did not cause significant changes in the hemodynamic and renal excretory functions. In the normotensive rats, receiving the high dose of the drug, mean urine osmolarity declined nearly 10-fold from 2466 +/- 136 to 290 +/- 37 mOsl while total solute excretion doubled. Infusion of the vehicle alone did not cause significant changes in the hemodynamic and renal excretory functions. The drug appears to have a primary action on the renal tubular handling of water and sodium. It may inhibit the secretion of antidiuretic hormone or block the antidiuretic hormone-stimulated cAMP-dependent increase in water permeability of the collecting tubules through its alpha 2-adrenoceptor agonistic effect. Natriuresis may have resulted in part from a lowered sympathetic tone to the kidneys.
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PMID:Guanabenz action on renal excretory function in New Zealand genetically hypertensive rats. 177 35

The cellular signaling mechanism of adenosine action has been studied in highly purified populations of cultured cells from the rabbit medullary thick ascending limb of Henle's loop (MTAL). The effects of specific adenosine-receptor agonists 5'(N-ethylcarboxamido)adenosine (NECA; A2) and N6-cyclohexyladenosine (CHA; A1) on basal and hormone-stimulated adenosine 3',5'-cyclic monophosphate (cAMP) production, cytosolic free calcium concentration ([Ca2+]f), and formation of inositol phosphates were examined. Production of cAMP was stimulated by high doses of NECA and was inhibited by low doses of CHA. The inhibitory effect of CHA was observed in cells in which cAMP production was first stimulated with vasopressin, isoproterenol, prostaglandin E2 (10(-6) M), or calcitonin (100 ng/ml) and was abolished by pretreating the cells with pertussis toxin (PT) for 12-20 h. A highly selective adenosine A1 antagonist, 8-cyclopentyl-1,3-dipropylxanthine (CPX), also abolished the inhibitory effect of CHA. Both NECA and CHA induced a rapid (10 s) and transient increase in [Ca2+]f, and this was associated with an increased inositol trisphosphate (IP3) production. Single-cell [Ca2+]f measurements indicated that all MTAL cells responded to CHA. The removal of extracellular Ca2+ failed to inhibit these responses. Pretreatment with PT or administration of CPX abolished both the increase in [Ca2+]f and the formation of IP3 occurring in response to CHA and NECA. Our results suggest that both adenylate cyclase-coupled inhibitory (A1) and stimulatory (A2) adenosine receptors are present in pure populations of cultured MTAL cells. Moreover, activation of an adenosine receptor coupled to a PT substrate results in the increased production of inositol phosphate and elevation of [Ca2+]f.
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PMID:Effects of adenosine on cAMP production and cytosolic Ca2+ in cultured rabbit medullary thick limb cells. 184 67

The effect of ethanol on receptor-mediated phospholipase C-linked signal transduction processes was investigated in isolated rat hepatocytes. Pretreatment of the cells with ethanol (6-300 mM) markedly inhibited a subsequent stimulation of phospholipase C by vasopressin, angiotensin II, or epidermal growth factor. By contrast, the effects of the alpha 1-adrenergic agonist phenylephrine and of glucagon were not affected by ethanol pretreatment. Ethanol inhibited the agonist-induced decrease in polyphosphoinositides, the formation of inositol phosphates, and the increase in cytosolic free Ca2+ levels, as detected with the intracellular Ca2+ indicator indo-1. The effects of ethanol were concentration dependent and were pronounced at low concentrations of agonists but were not significant at saturating levels. Pretreatment of the cells with the protein kinase C inhibitor H7 partly prevented the inhibition by ethanol of vasopressin-induced phospholipase C activation. By contrast, pretreatment of the cells with (Rp)-adenosine cyclic 3':5'-phosphorothioate [Rp)-cAMP-S), a competitive inhibitor of protein kinase A, potentiated the inhibitory effect of ethanol on the Ca2+ mobilization by vasopressin. (Rp)-cAMP-S similarly potentiated the inhibition of phospholipase C by the protein kinase C-activating phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA). The kinase A inhibitor also made the Ca2+ mobilization by phenylephrine sensitive to ethanol, indicating that the formation of cAMP in the cells played a role in suppressing the sensitivity to ethanol. Pretreatment of the cells with ethanol enhanced the inhibitory effects of TPA on the vasopressin-induced phospholipase C activation at all concentrations of the hormone; however, these synergistic effects were prevented when TPA was added prior to ethanol, a condition that prevents the activation of phospholipase C by ethanol. The data indicate that ethanol causes desensitization of the receptor-mediated phospholipase C secondary to the ethanol-induced activation of phospholipase C and activation of protein kinase C. Ethanol treatment also affects the sensitivity of the phospholipase C system to control by protein kinases A and C. The data indicate that ethanol can affect the control of intracellular signal transduction processes in liver cells under physiologically relevant conditions.
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PMID:Ethanol causes desensitization of receptor-mediated phospholipase C activation in isolated hepatocytes. 184 16

Swelling of hepatocytes increases the concentration of inositol 1,4,5-trisphosphate, Ca2+ and cAMP, without activating glycogen phosphorylase. In these hepatocytes, the activation of phosphorylase by suboptimal concentrations of vasopressin or angiotensin II was partly antagonized.
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PMID:Hepatocyte swelling increases inositol 1,4,5-trisphosphate, calcium and cyclic AMP concentration but antagonizes phosphorylase activation by Ca2(+)-dependent hormones. 184 8

Studies were conducted to clarify the effects of noradrenaline on oleate metabolism in isolated hepatocytes from fed rats. Noradrenaline caused an inhibition of ketogenesis from oleate along with a stimulation of glucose release through alpha 1-adrenergic receptors. Anti-ketogenic action of noradrenaline was confirmed by the suppression of the formation of radioactive acid-soluble products from [1-14C]oleate in response to this agent. Noradrenaline increased the conversion of [1-14C]oleate into 14CO2 but failed to affect [1-14C]oleate esterification. When hepatocytes were incubated in a medium containing 1 mM EGTA but no Ca2+, the effects of noradrenaline on oleate oxidation were negated. On the other hand, noradrenaline-induced increase in glucose release remained unchanged even in the absence of Ca2+ in the incubation medium. Decrease in ketogenesis and increase in glucose release produced by vasopressin was completely abolished by calcium depletion. Noradrenaline caused a significant increase in cAMP levels in both the presence and absence of Ca2+, although the effect was more marked in the latter. Vasopressin did not affect it. The noradrenaline-induced increase in cAMP and glucose release in the absence of Ca2+ was also mediated by alpha 1-adrenergic receptors. These data are discussed and it is suggested that alpha 1-adrenergic agonists may control hepatic ketogenesis and glycogenolysis through two separate signal transduction mechanisms, i.e., a calcium-mobilizing system which is common with vasopressin, and a cAMP generation system which vasopressin lacks.
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PMID:Alpha 1-adrenergic regulation of ketogenesis in isolated rat hepatocytes. 184 21

The precise mechanistic role of the cAMP-dependent protein kinase (cAMP-PK) in cAMP-mediated gene induction remains unclear. Renal epithelial cell mutants were compared to the LLC-PK1 parental cell line for induction of the cAMP-responsive urokinase-type plasminogen activator (uPA) gene, as quantitated by the technique of mRNA solution hybridization. The FIB4 and FIB6 mutants, which possess less than 10% parental cAMP-PK catalytic (C) subunit activity, showed markedly diminished uPA mRNA induction in response to agents elevating intracellular cAMP such as the cAMP analogue 8-bromo-cAMP and the adenylate cyclase-stimulating hormones vasopressin and calcitonin. In contrast, the mutant cells responded to a similar or greater extent than the parental cells in terms of uPA mRNA induction following treatment with the Ca2+/phospholipid-dependent protein kinase activator phorbol 12-myristate 13-acetate (PMA). Elevation of intracellular cAMP was found to induce a translocation of the cAMP-PK C subunit from the perinuclear Golgi region to the nucleus in both parental and mutant cell lines, as shown by immunocytochemical techniques. Results argue for the role of the cAMP-PK C subunit activity and possibly nuclear translocation of the C subunit in cAMP-mediated uPA induction, which is mechanistically distinct from the PMA-stimulated response.
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PMID:Mechanisms of cAMP-mediated gene induction: examination of renal epithelial cell mutants affected in the catalytic subunit of the cAMP-dependent protein kinase. 189 92

Previous studies with the rhodamine phalloidin binding assay have shown that antidiuretic hormone and 8-Br-cAMP rapidly depolymerize F-actin in toad bladder epithelial cells. We have extended these studies with the DNAse inhibition assay and have found that in isolated epithelial cell suspensions, G-actin increases from 37 to 56% of total actin following 8-br-cAMP stimulation. The G-actin concentration in the epithelial cell greatly exceeds its critical concentration, indicating the requirement for a G-actin sequestering protein or proteins in this system.
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PMID:Actin depolymerization in the cyclic AMP-stimulated toad bladder epithelial cell, determined by the DNAse method. 190 49

This paper summarizes the recent knowledge on the factors stimulating or inhibiting the adrenocortical growth. In the part I of the present review the following stimulatory growth factors are discussed: ACTH--in vivo, N-POMC derivatives, dibutyryl cAMP--in vivo, GH, Prl, vasopressin, oxytocin, insulin, insulin-like growth factor I (somatomedin C), estradiol and vasoactive intestinal polypeptide (VIP). Among the factors, which inhibit the adrenocortical growth, the following ones are considered: ACTH--in vitro, cAMP--in vitro, adrenal steroids and testicular androgens. The remaining hormones and factors affecting the adrenocortical growth are described in the part II of the review.
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PMID:[Factors stimulating and/or inhibiting growth processes of the adrenal cortex. I. The role of the anterior pituitary and hypothalamic hormones, insulin, sex steroids and certain neuropeptides]. 194 99


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