Influence of steroids in vitro on transaminase activity and integrity of thymocytes.

Abstract

Studies have been conducted on the effects of steroids added in vitro on the glutamic-aspartic and glutamic-alanine transaminase activities of rat thymocytes. Testosterone, progesterone, deoxycorticosterone and 17α-ethyl-19-nortestosterone, each in approximately 10−4 M concentration, increased glutamic-aspartic transaminase activity. Added cortisol produced a decrease in this enzymic activity of thymocytes when studied by 1 of the 3 transaminase methods used; assays by the other 2 procedures revealed no influence of this steroid. The low level of glutamic-alanine transaminase activity of thymocytes was unaltered by any of the steroids studied. There was no steroidal effect on the transaminase activity of brokencell preparations of thymocytes. The same basal transaminase activity was observed in thymocytes obtained from weanling and from post-pubertal rats. The steroidal effects were the same on cells from both age groups. Balance studies of intact thymocytes and incubation medium and experiments with brok...