Potentiation of des-Arg9-kallidin-induced vasoconstrictor responses by metallopeptidase inhibition in isolated human umbilical artery.

Several metallopeptidases have been reported to be involved in bradykinin (BK) B(1) receptor agonist metabolism. Our goal was to evaluate in vitro roles of metallopeptidases [e.g.

Characterization of 5-HT receptor subtypes mediating contraction in human umbilical vein. 2. Evidence of involvement of 5-HT1B receptors using functional studies.

Previous studies have shown that a heterogeneous 5-HT receptor population may be involved in vasoconstrictor actions of 5-HT in human umbilical vein (HUV). The aim of the present study was to evaluate whether the 5-HT(1B/1D) receptor subtype mediates contraction in this tissue. 5-HT(1B/1D)-mediated responses can be enhanced or unmasked after exposure to threshold or sub-threshold KCl concentrations.

Characterization of 5-HT receptor subtypes mediating contraction in human umbilical vein. 1. Evidence of involvement of 5-HT2A receptors using functional and radioligand binding assays.

This study attempted to characterize pharmacologically the involvement of 5-HT(2A) receptors in 5-HT-induced contractile responses in human umbilical vein (HUV) rings employing functional and radioligand binding assays. In HUV rings, prazosin 1 micro M did not affect contractile responses elicited by 5-HT, ruling out the involvement of alpha(1)-adrenoceptors in contractile responses to 5-HT. 5-HT-induced contractions were competitively blocked by ketanserin, a 5-HT(2A)-selective antagonist.