[Effect of insulin and hydrocortisone on the isoenzyme composition of pyruvate kinase in the rabbit kidney].

Alloxan diabetes, starvation of rabbits within one day and administration of hydrocortisone during 5 days did not cause distinct alterations in the total activity of pyruvate kinase in kidney cortex. At the same time pronounced alterations in the isozyme spectra were observed: the L-type activity of pyruvate kinase was decreased and the M2-type of activity was increased. The total activity and the isozyme content of pyruvate kinase were only slightly altered in starvation of rabbits during 3 or 10-16 days and after administration of protamine-Zn-insulin during 3 days. Hydrocortisone caused variable effects on the pyruvate kinase isozymes from kidney cortex, depending on periods of administration.