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 quality of the postjunctional alpha adrenoceptors involved in the increase in diastolic pressure caused by 2-N,N-dimethylamino-5, 6-dihydroxy-1,2,3,4-tetrahydronaphthalene (M-7) were re-evaluated in pithed normotensive rats. The antagonism by yohimbine (1 mg/kg) was most pronounced, whereas prazosin (0.1 mg/kg) had no effect on the hypertensive responses to low doses of M-7, but clearly attenuated those to the higher amounts (greater than 10 micrograms/kg i.v.). A pretreatment with the combination of both alpha adrenoceptor antagonists markedly depressed slope and maximum of the log dose-pressor response curve to M-7. The selective beta-2 adrenoceptor antagonist ICI 118, 551 caused an enhancement of the pressor effects of the higher doses of M-7 which was most profound after the combined treatment with prazosin and yohimbine. M-7 showed a dose-dependent depressor effect in phentolamine (30 mg/kg)-treated pithed rats of which diastolic pressure was raised by infusion of vasopressin. It is concluded that M-7, in addition to its reported alpha-2 adrenoceptor agonistic properties, stimulates postsynaptic alpha-1 adrenoceptors in higher doses. In pithed normotensive rats, however, M-7 also interacts with vascular beta-2 adrenoceptors giving rise to vasodilatation. This action can strongly interfere with the vasoconstrictor effect of M-7.
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PMID:Re-evaluation of the selectivity of 2-N,N-dimethylamino-5,6-dihydroxy-1,2,3, 4-tetrahydronaphthalene (M-7) as an agonist of postjunctional alpha-2 adrenoceptors in the pithed normotensive rat. 613 92

The effects of both dopamine and enkephalin agonists were assessed on electrically stimulated vasopressin secretion from the isolated neural lobe. Both dopamine (10(-6) M) and the dopamine agonist ADTN (2-amino-6,7-dihydroxy-1,2,3,4-tetrahydronaphthalene; 10(-6) M) significantly reduced the stimulated release of vasopressin. This reduction in vasopressin secretion was prevented by the dopamine antagonist sulpiride (10(-6) M). [D-Ala2, D-Leu5]Enkephalin (DADLE) also inhibited vasopressin release and its effect was additive to that of ADTN. The effect of DADLE was prevented by the opiate antagonist naloxone and was also sensitive to the calcium content of the medium. Low calcium concentrations markedly increased the inhibitory effect of DADLE, while high concentrations abolished its effect. These findings provide evidence of a direct inhibitory action of both dopamine and enkephalins at the level of the neural lobe and suggest that the effect of enkephalins may be intimately related to calcium-sensitive neurosecretory events.
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PMID:Dopamine and [D-ALA2, D-Leu5]enkephalin inhibit the electrically stimulated neurohypophyseal release of vasopressin in vitro: evidence for calcium-dependent opiate action. 703 79