Influence of Major Surgical Stress on Plasma Levels of Testosterone, Luteinizing Hormone and Follicle-Stimulating Hormone in Male Patients

Abstract

Effects of major surgical stress on plasma concentrations of testosterone and immunoreactive luteinizing hormone (LH) were studied in 25 male patients. Significantly decreased levels of testosterone from the pre-operative level (0.66 ± 0.03 (se) μg/100 ml) were found during the operation. On the other hand, plasma LH increased significantly from the pre-operative level [4.27 ± 0.29 (se) μg/100 ml] during the operation and reached the maximum concentration 30 min after the beginning of incision [8.28 ± 0.71 (se) μg/100 ml]. Shortly after the end of the operations, the mean concentration of LH had returned to its pre-operative level, but the mean concentration of testosterone continued to fall. No such change explainable by diurnal variation was observed in 10 male patients followed for a similar period of time prior to surgery. The patients exhibited a significant fall in LH concentration on the 2nd post-operative day [3.11 ± 0.24 (se) μg/100 ml], when plasma testosterone showed the most marked decrease [0.21 ± 0.03 (se) μg/100 ml]. Plasma levels of immunoreactive follicle-stimulating hormone examined in 9 of the 25 patients, showed no significant changes under surgical stress. These observations suggest that there may be some lack of testicular sensitivity to gonadotrophins during and following major surgery, though a shift in the androgen biosynthetic pathway of the testis may be considered.