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)

Stimulation of angiotensin II AT2 receptors has been shown to inhibit AT1 receptor-mediated actions in peripheral tissues. The role of AT2 receptors in the central actions of angiotensin is not well understood. In the present study, plasma vasopressin levels and water intake in response to intracerebroventricular angiotensin II (10 pmol) were determined after intracerebroventricular pretreatment with PD 123177 (1-(4-amino-3-methylphenyl)methyl-5-diphenylacetyl-4,5,6,7-tetrahy dro-1H- imidazo[4,5-c]pyridine-6-carboxylic acid-2HCl), a selective AT2 receptor antagonist (10, 100 and 1000 pmol), or with losartan (2-n-butyl-4-chloro-5-hydroxy-methyl-1-2'-(1H-tetrazole-5-yl)biphenyl-4- yl)methylimidazole, potassium salt), a specific AT1 receptor antagonist (0.2, 2 and 10 nmol). Blood samples for vasopressin determination were drawn 90 s after angiotensin II injection and the drinking response was determined in a time interval of 10 min after intracerebroventricular angiotensin II. Losartan at a dose of 2 nmol or higher completely prevented vasopressin release and drinking response to angiotensin II. The drinking response was already attenuated after pretreatment with the lowest dose of losartan. In contrast, PD 123177 potentiated the angiotensin II-induced vasopressin release (39.7 +/- 2.7 pg/ml after 1000 pmol PD 123177 vs. 21.3 +/- 2.9 pg/ml in vehicle-pretreated controls, P < 0.05). The dipsogenic response to angiotensin II was also potentiated by PD 123177 (9.5 +/- 0.7 ml after 1000 pmol PD 123177 vs. 5.1 +/- 1.3 ml in vehicle-pretreated controls, P < 0.05). Our results suggest that the angiotensin II-induced vasopressin release and drinking, mediated by central AT1 receptors, are under inhibitory control by central AT2 receptors.
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PMID:Angiotensin AT1 receptor-mediated vasopressin release and drinking are potentiated by an AT2 receptor antagonist. 776 95

Recently, we have shown that angiotensin II-induced AT1 receptor-mediated vasopressin release can be potentiated by blockade of periventricular AT2 receptors. In the present study, we investigated whether the AT2 receptor also exerts an inhibitory effect on osmotically induced vasopressin release. In addition, we tested the effect of the muscarinic receptor antagonist, atropine, on hyperosmolar saline-induced vasopressin release. Plasma vasopressin levels were determined 90 s after intracerebroventricularly applied hyperosmolar saline (0.2, 0.3 and 0.6 M, 5 microliters) with or without intracerebroventricular pretreatment with 1 nmol of the selective AT2 receptor antagonist, PD 123177 (1-(4-amino-3-methylphenyl)methyl-5-diphenylacetyl-4,5,6,7-tetrahy dro- 1H-imidazo[4,5-c]pyridine-6-carboxylic acid-2HCl), or with 15 nmol of the muscarinic receptor antagonist, atropine. PD 123177 potentiated 0.2 M saline-induced vasopressin release (4.7 +/- 0.8 pg/ml vs. 2.2 +/- 0.3 in vehicle-pretreated controls, P < 0.05), did not affect 0.3 M saline-induced vasopressin release (4.3 +/- 0.7 pg/ml vs. 5.4 +/- 0.6 pg/ml in vehicle-pretreated controls) and reduced 0.6 M saline-induced vasopressin release (10.0 +/- 2.3 pg/ml vs. 17.9 +/- 1.8 pg/ml in vehicle-pretreated controls, P < 0.05). Pretreatment with atropine reduced 0.3 M (2.3 +/- 0.6 pg/ml vs. 5.4 +/- 0.9 pg/ml in vehicle-pretreated controls, P < 0.05) and 0.6 M saline-induced AVP release (4.0 +/- 1.5 pg/ml vs. 18.4 +/- 2.4 pg/ml in vehicle-pretreated controls, P < 0.05) but did not affect 0.2 M saline-induced vasopressin release (2.1 +/- 0.4 pg/ml vs. 3.2 +/- 0.8 pg/ml in vehicle-pretreated controls). Our results suggest that the low saline concentration-induced, AT1 receptor-mediated, vasopressin release is under inhibitory control by periventricular AT2 receptors. Following high saline concentrations, a muscarinic mechanism seems to be predominant on which AT2 receptor stimulation acts in a facilitating manner.
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PMID:Effect of angiotensin AT2 and muscarinic receptor blockade on osmotically induced vasopressin release. 874 Nov 76