Relative Resistance to the Hypertensive Effects of Desoxycorticosterone During Active Phase of Renal Compensatory Hypertrophy

¹ From the Carter Physiology Laboratory, The University of Texas Medical Branch, Galveston, Texas

An attempt was made to ascertain the circumstances under which unilateral nephrectomy maximally sensitized rats to hypertensive cardiovascular disease induced by desoxycorticosterone acetate in the presence of augmented NACl intake. The experiments showed that animals in which hormone treatment was delayed until 2 weeks after uninephrectomy were much more sensitive than animals in which hormone treatment was begun on the day of kidney removal. This was indicated by earlier onset and greater severity of hypertension; by a larger percentage of animals in such groups being affected, and by a greater incidence and severity of cardiovascular lesions in the former as compared with the latter. The much greater kidney size of the former clearly makes it difficult to ascribe the greater sensitivity to a reduction in renal mass as such. It is thought that during active compensatory renal hypertrophy the renal tubules are probably less responsive to the action of the hormone and therefore less prone to develop sodium retention and hence hypertension.