BRADYKININ-INDUCED VENODILATION IS NOT IMPAIRED WITH AGING IN HUMANS

The aim of this study was to determine whether there is an age-related decline in vascular responsiveness to bradykinin, whose vasodilatory action is mediated chiefly through endothelium-derived relaxing factor (EDRF). Dose-response curves for bradykinin were constructed using the dorsal hand vein compliance technique in veins preconstricted with phenylephrine in 27 volunteers (16 male, 11 female) aged 18 to 81 years. At the end of the bradykinin study, 12 subjects had a single infusion of a high dose of isoproterenol. There was no correlation between age and the E(MAX) or the log ED50 for bradykinin, although the same subjects showed a correlation between age and the E(MAX) for isoproterenol, as previously found. There was no significant difference in either the E(MAX) or the log ED50 between male and female subjects. The results suggest that bradykinin-induced vasodilation is independent of age or gender.