Influence of Ketamine and Propranolol On Plasma-renin Activity (pra) in Female Rabbits and Guinea-pigs

1-degrees Plasma renin activity was measured in non pregnant rabbits and guinea pigs under Ketamine-induced general anesthesia after pretreatment either with Propranolol or with a Placebo. Study was performed using a radio-immunoassay for angiotensin I. 2-degrees Twenty minutes after the beginning of the observation period, renin activity in rabbits who had received Placebo alone (11.47 +/- 2.35 ng/ml/h) or associated with Ketamine (11.36 +/- 2.54 ng/ml/h) was similar. However, enzyme activity was significantly lower (P < 0.001) when Propranolol was associated with Ketamine (3.97 +/- 0.58 ng/ml/h) or with Placebo (4.10 +/- 0.55 ng/ml/h). 3-degrees In the same way, renin activity was significantly higher (P < 0.001) in guinea pigs without Propranolol than in those who had received this drug. 4-degrees These findings indicate that stress induced by general anesthesia with Ketamine or by simple manipulation of animals (Placebo) was accompanied by an excessive increase in plasma renin activity. Propranolol maintained the level of this enzyme activity within normal limits.