Increase in Serum Ribonuclease Activity After Bilateral Nephrectomy

Serum ribonuclease activity increased after bilateral nephrectomy or hydronephrosis in the rat. This increase could be shown to occur 40 minutes after bilateral nephrectomy and was not abolished by either simultaneous adrenalectomy, pancreatectomy, evisceration or cortisone administration in single or repeated doses. As a similar enzyme was found in the urine, it is suggested that the increased serum activity is due to nonexcretion by the kidneys. The results also indicate that the increased activity did not originate from the digestive tract, pancreas or lymphoid tissues, and that stress did not play a major role in the phenomenon.