Unchanged testosterone production rates in growth hormone-treated healthy men.
The effect of biosynthetic human GH on the production rates of testosterone was determined in healthy men (n = 7) using the stable isotope dilution technique and mass spectrometry. 1Alpha,2alpha-d-testosterone (20 microg/h) was infused for 10 h (0800-1800 h). Blood samples obtained at 20-min intervals from 1400-1800 h were pooled during two 2-h periods. Subsequently, each volunteer received a daily dose of biosynthetic human GH (4 IU/day sc) for 7 days. This resulted in a rise in plasma concentrations of somatomedin-C from, basal, 0.67+/-0.13 U/mL to 1.20+/-0.2 U/mL on day 7 (P < 0.0001). Testosterone production rates (basal: 209.9+/-31.0 microg/h) were unchanged by treatment with GH (day 7: 192.2+/-30.1 microg/h). In healthy men, short-term treatment with sc GH does not influence endogenous testosterone production rates.
Department of Internal Medicine III, University of Vienna, Austria. h.vierhapper@akh-wien.ac.at
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D000328:Adult; D008401:Gas Chromatography-Mass Spectrometry; D006706:Homeostasis / Q000502:physiology; D019382:Human Growth Hormone / Q000494:pharmacology*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D008297:Male; D009994:Osmolar Concentration; D012016:Reference Values; D013739:Testosterone / Q000096:biosynthesis* / Q000097:blood
D019382:Human Growth Hormone; D013739:Testosterone; D007334:Insulin-Like Growth Factor I