RECEPTORS FOR KININS IN THE HUMAN ISOLATED UMBILICAL VEIN

Citation
F. Gobeil et al., RECEPTORS FOR KININS IN THE HUMAN ISOLATED UMBILICAL VEIN, British Journal of Pharmacology, 118(2), 1996, pp. 289-294
Citations number
28
Categorie Soggetti
Pharmacology & Pharmacy",Biology
ISSN journal
00071188
Volume
118
Issue
2
Year of publication
1996
Pages
289 - 294
Database
ISI
SICI code
0007-1188(1996)118:2<289:RFKITH>2.0.ZU;2-0
Abstract
1 The human umbilical vein has been found to contract in response to b radykinin (BK) and desArg(9)BK. 2 The rank order of potency of agonist s, in the presence of the B-1 receptor antagonist Lys[Leu(8)]desArg(9) BK, is as follows: [Hyp(3),Tyr(Me)(8)]BK (pD(2) 8.88)=[Hyp(3)]BK (pD(2 ) 8.86)=LysBK (pD(2) 8.81) greater than or equal to BK (pD(2) 8.60) mu ch greater than [Aib(7)]BK (pD(2) 6.38) much greater than desArg(9)BK and LysdesArg(9)BK (inactive). 3 Hoe 140 (pA(2) 8.42) inhibits the eff ects of BK while other B-2 receptor peptide antagonists are very weak and WIN 64338 is practically inactive. 4 Venoconstrictor responses to desArg(9)BK of fresh tissues increase with time during the in vitro in cubation and reach a maximum after 4-6 h. The activity of Hoe 140 (pA( 2) 5.48) is negligible against B-1 receptor agonists. 5 When measured in the presence of the selective B-2 receptor antagonist Hoe 140 (400 nM), the order of potency of kinin related peptides on the B-1 recepto r is Lys[desArg(9)]BK (pD(2) 8.60) > desArg(9)BK (pD(2) 6.69). BK, Lys BK, [Hyp(3)]BK and other B-2 receptor agonists are inactive. 6 The B-1 receptor antagonist, Lys[Leu(8)]desArg(9)BK (pA(2) 7.99), inhibits th e response of the human vein to B-1 receptor agonists (LysdesArg(9)BK or desArg(9)BK), but do not alter the effect of BK. 7 The results summ arized in this paper indicate that the human isolated umbilical vein i s a sensitive preparation containing both B-1 and B-2 receptors. The h uman B-2 receptor shows some similarity with that of the rabbit (at le ast for agonist potencies) and differs from the B-2 receptor of the gu inea-pig. Compared to the rabbit B-1 receptor, the human B-1 receptor shows low sensitivity to peptides that lack the N-terminal Lys.