Abstract
This study was undertaken to investigate the effects of Althesin and surgery on plasma concentrations of luteinizing hormone (LH) and testosterone in 10 male patients. Plasma LH concentrations increased markedly during Althesin anaesthesia given alone over a period of 45 min. The high concentration lasted for 30 min after the start of surgery and was followed by a gradual decrease, although the concentration remained significantly greater than the control value. Plasma testosterone concentrations decreased during Althesin anaesthesia, and a further decrease was noted during the period following surgery.