Binding of [3H]des-Arg9-BK to rabbit anterior mesenteric vein

Publisher Website
Google Scholar
Abstract
Binding studies of [3H]des-Arg9-BK [[3H]des-Arg9-bradykinin] were performed on pieces of rabbit anterior mesenteric veins. Kinetic studies permitted the evaluation of an affinity constant of 1.04 .times. 10-7 M, which is not so different from the apparent affinity constant determined by bioassay (1.6 .times. 10-7 M). Inhibition of the binding of [3H]des-Arg9-BK with various kinins [Lys-BK, BK, Tyr(Me)8-BK and Leu8-des-Arg9-BK] results in an order of potency of kinins very similar to that observed in the bioassay. These binding sites may be the same as those subserving the biological action of des-Arg9-BK (pharmacological receptors). The preincubation of tissues in Krebs'' solution brings about an increase of the specific binding from 0.06 pmol/mg of wet wt at time 0-0.75 pmol after 24 h; cycloheximide inhibits this increase for at least 6 h. Veins taken from animals treated with Escherichia coli LPS [lipopolysaccharide], which show an increase in sensitivity compared with veins extracted from untreated animals, have a higher number of specific binding sites for [3H]des-Arg9-BK. The increased response of tissues to des-Arg9-BK is apparently due to the de novo synthesis of receptors from kinins in some experimental and pathological conditions.

This publication has 3 references indexed in Scilit: