Anomalies de l'axe somatotrope et usage abusif d'hormone de croissance (GH)

Abstract

Aims. – To evaluate the effects of the doping by GH. Synthesis of facts. – If it is well known that GH treatment has benefic effects on body composition in GH deficient patients (decrease in fat mass and increase in muscle mass), nothing has been proved on doping effects in trained subjects, excepted perhaps to avoid protein catabolism. GH amounts use for doping might be supraphysiological doses and might potentiate other substances such as anabolic steroids. Adverse effects are not yet well described, but seem potentially important at vascular and tumoral levels. Recombinant human GH (rhGH) abuse in athletes is actually almost undetectable because rhGH has the same sequence than natural GH, with a very short biological half-life and important fluctuations in plasmatic concentration, moreover urinary GH excretion is modified by physical exercise. It is therefore needful to analyze GH concentration in plasma (22 and 20 kDa molecular forms, the 20 kDa secretion is inhibited by feedback by the exogenous recombinant 22 kDa GH) as well as secondary markers, including IGF1, IGFBP3 and ALS. Reference values should be established taken into account physical activity type, and age.