In vivo activation of renal phospholipase activity by bradykinin in the rat.

Activation of a renal acylhydrolase by bradykinin (BK) with subsequent release of prostaglandins precursor arachidonic acid has been postulated but not yet demonstrated. BK was infused into the left artery of 27 rats which were subdivided into 9 groups according to BK concentration (10, 100 and 1000 ng/min) and time of infusion (20, 40 and 60 min). The rats were then sacrificed and the left to right ratio of renal phospholipase activity was determined. The data obtained were processed by a factorial analysis of variance which allowed the effect of BK and the time of infusion to be evaluated independently as well as interdependently. The results of the statistical analysis showed that phospholipase activity depends on both BK dosage and infusion time and that there is no interaction between dose and time. These findings offer evidence for the "in vivo" activation of the kidney phospholipase activity by BK.