Serum ribonuclease activity in acute myocardial infarction

Ribonuclease (RNase) activity measured at pH 7.8 (the alkaline RNase) and pH 6.7 (the acid RNase) was estimated in serum of 54 patients with acute myocardial infarction (AMI). The estimations were performed on the first day of disease, then on the seven consecutive days and on the 14th day. A significant elevation in both alkaline and acid RNase activities on days 1--7 of AMI was found, compared with healthy control subjects. Elevation in both acid and alkaline RNase activity began on the 1st day of AMI and continued to increase up to peak values on the 3rd day for acid RNase and the 5 the day for alkaline RNase. On the 14th day both alkaline and acid RNase activities came back to the range found in normal sera. Increase in serum acid and alkaline RNase activity in AMI showed a time pattern different from that of GOT and GPT aminotransferases. However, the relationship between the elevation of serum RNase activity and severity of the disease was obvious.