title: Contribution of bradykinin to maintenance of normal blood pressure.
abstract: The purpose of these experiments was to investigate whether the vasodilator tissue hormone bradykinin contributes to the maintenance of normal blood pressure. A newly synthesized peptide competitive antagonist of bradykinin, the compound Arg-Pro-Hyp-Gly-Phe-Ser-DPhe-Phe-Arg-trifluoracetic acid (B3852), capable of inhibiting the depressor effect of exogenous bradykinin by over 50%, was infused into 10 normotensive rats at a rate of 500 micrograms/0.1 ml/min. Blood pressure rose immediately, from a baseline of 104 +/- 5 to 131 +/- 7 mm Hg at the end of a 5-minute infusion, and returned to baseline within 2 to 3 minutes after discontinuation of the infusion. When similar doses were administered by continuous infusion to previously nephrectomized rats (n = 5) or as an acute bolus to adrenalectomized rats (n = 5), blood pressure rose from 111 +/- 3 to 125 +/- 5 mm Hg and from 112 +/- 4 to 128 +/- 5 mm Hg, respectively. The data suggest that a vasodepressor action of endogenous bradykinin contributes to maintenance of normal peripheral vascular tone, and that this action is not mediated through adrenal catecholamines or renomedullary prostaglandins.
mesh_terms: D000818:Animals; D001794:Blood Pressure; D001920:Bradykinin / Q000031:analogs & derivatives / Q000494:pharmacology / Q000502:physiology*; D005463:Fluoroacetates; D008297:Male; D010865:Pilot Projects; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D005463:Fluoroacetates; C052791:B 3852; D001920:Bradykinin