[Depression of testosterone secretion in male patients with respiratory failure]

To investigate the changes of testosterone (T) secretion under sustained hypoxia, we determined basal levels of urine T, 17 ketosteroid, luteinizing hormone releasing hormone (LHRH), luteinizing hormone (LH), follicle stimulating hormone (FSH) and response to LHRH and HCG (human chorionic gonadotropin) in male patients with respiratory failure. After evaluating blood gas data, we also measured serum T, LH, FSH, plasma progesterone (P) and 17 hydroxyprogesterone (17OH-P). The subjects were divided into 3 groups according to PaO2; Group 1 with a PaO2 under 60 Torr, Group 2 with a PaO2 between 60 Torr and under 70 Torr, Group 3 was an age-matched control group. Urine T and serum T were significantly lower in Group 1 compared with those of Group 3. In the LHRH test, augmented relative responsiveness and delayed peak value in LH secretion were observed in Group 1, compared with those of Group 3. As for the HCG test, no differences were observed among the 3 groups. The ratio of 17OH-P to P, which indicates activity of 17-hydroxylase, was observed to be diminished with increasing degrees of hypoxia. These data suggest that in male patients with respiratory failure there was depression in T secretion as well as 17-hydroxylase activity due to hypothalamic-pituitary hypofunction.