Protein kinase C activity in compensatory kidney growth.

Very little information exists about the intracellular mechanisms mediating remnant kidney hypertrophy after reduction of renal mass. The present experiments demonstrate that the activity of a key enzyme in cellular proliferation, protein kinase C, is enhanced in the kidney during post-uninephrectomy hypertrophy. As additional evidence of "in vivo" enzyme activation, the enzyme activity migrates from the cytosolic to the particulate fraction of the cells and the number of sites of phorbol dibutyrate binding is enhanced in kidney membranes 24 hr after contralateral nephrectomy. The stimulation of the enzyme is higher than the increase in kidney weight, although both phenomena are linearly related.