Effect of hypophysectomy upon renal kallikrein-kinin system in rats.

It is confirmed that urinary kallikrein is significantly and persistently decreased in totally hypophysectomized rats. In addition, kallikrein activity in the kidneys in these animals is significantly reduced (p less than .001) as compared to partially hypophysectomized and sham-operated rats. The administration of 125 mU of ACTH twice a day for 2 months, did not modify urinary kallikrein excretion. Negative effects were also obtained in subsequent periods, by injection of 10 microgram corticosterone and 10 microgram aldosterone, twice a day for 9 and 6 days, respectively. The administration of rat pituitary anterior lobe homogenates, freshly prepared, increased significantly urinary kallikrein level in hypophysectomized rats.