Cellular hypertrophy and renal function during compensatory renal growth

Abstract

Simultaneous measurements of biochemical and physiological events of compensatory renal hypertrophy were made in groups of white Spartan rats. Thirty hours following right unilateral nephrectomy, the left kidney had an increased rate of renal plasma flow, glomerular filtration rate, and K excretion when compared to sham-nephrectomized rats. Kidney cells were also hypertrophied as evidenced by an increase in the ratio of RNA to DNA. The effects of a single injection of cycloheximide and actinomycin D on compensatory growth were studied. Both drugs prevented the rise in glomerular filtration rate and renal plasma flow 30 h postnephrectomy while having no inhibitory effect on cell hypertrophy. The maintenance of nephrectomized rats on a low-Na diet also interfered with the physiological components of the response while having no effect on RNA or DNA. The physiological and biochemical aspects of compensatory renal hypertrophy may be under separate control systems.