Effects of Hypophysectomy and Growth Hormone on Renal Compensatory Hypertrophy in Rats.

Abstract

Summary The effect of hypophysectomy on renal compensatory hypertrophy (RCH) was observed in unilaterally nephrectomized rats receiving no therapy and those receiving replacement therapy and was compared to the RCH attained by non-hypophysectomized unilaterally nephrectomized rats at 2, 5, and 10 days. In the latter group there was an initial rapid RCH seen at day 2 which continued, but at a slower rate, through day 10. In the hypophysectomized group without replacement therapy there was also an initial RCH in the first 48 hours. However, instead of the RCH continuing there was a regression in kidney size at 5 days and with no subsequent change at 10 days. In the hypophysectomized group receiving hormone replacement there was an initial RCH comparable to the other two groups, but the further renal enlargement at 10 days was much less than that of the non-hypophysectomized animals. The results of this experiment and of other reported studies imply the existence of a renotropic factor which is not produced in the pituitary, but which requires an intact pituitary for full effectiveness.