title: Hypotensive effects of the renin inhibitor (RI-78) and the converting enzyme inhibitor (teprotide) in conscious monkeys.
abstract: Effects of the pentapeptide renin inhibitor (RI-78; Phe(4Cl)-Phe-Val-Tyr-Lys-NH2) and the angiotensin converting enzyme (ACE) inhibitor (teprotide) on mean arterial pressure (MAP) were examined in conscious monkeys (M. fascicularis). In salt depleted normotensive monkeys with a MAP of 95 +/- 4 mmHg and plasma renin activity (PRA) of 15.9 +/- 2.7 ngAI/ml/h, a bolus injection of a dose of 375 micrograms/kg of RI-78 caused a prompt hypotensive effect. Maximal hypotensive action was seen within 1 min, and MAP returned to the basal level within 15 min. With this dose, MAP was reduced by 20 +/- 6 mmHg. Teprotide (1 mg/kg) decreased MAP and reached a nadir after 13 min. There was no significant difference between maximal hypotensive responses seen with RI-78 (375 micrograms/kg) and with teprotide (1 mg/kg). Hypotensive effects of RI-78 and teprotide were also examined in acute renal hypertensive monkeys with a MAP of 125 +/- 5 mmHg and a PRA of 27.1 +/- 5.7 ngAI/ml/h. Again, similar hypotensive effects were observed. We conclude that antihypertensive effect of RI-78 is comparable to that seen with teprotide.
mesh_terms: D000806:Angiotensin-Converting Enzyme Inhibitors; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D005260:Female; D006977:Hypertension, Renal / Q000503:physiopathology; D008252:Macaca fascicularis; D008297:Male; D009842:Oligopeptides / Q000494:pharmacology*; D013722:Teprotide / Q000494:pharmacology*; D000092502:Renin Inhibitors
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D009842:Oligopeptides; D013722:Teprotide; D000092502:Renin Inhibitors; C053171:RI 78