Somatomedin (SM) activity, GH, T3 and T4 were investigated in 6 girls with anorexia nervosa during hospitalization and at outpatient clinic. On admission, serum T3 (27-62ng/dl) and SM activity (0.24-0.55U/ml) were low in all cases, while basal GH was extremely high in 2 cases. A significant negative correlation was found between SM activity and basal GH during the course of treatment (r=-0.61, p<0.02). The change in SM activity was related to that of the serum T3 level and a significant positive correlation was found between SM activity and serum T3 (r=0.80, p<0.001).
These data suggest that decieased SM activity may suppress the inhibitory effect of SM on GH release and may raise the basal GH level. SM activity is one of the indicators of the nutritional condition in anorexia nervosa as well as the serum T3 concentration.