Acute and Long-Term Responses to hGH in Children with Idiopathic Small-for-Dates Dwarfism

Abstract

Studies of acute and long term respones to human growth hormone (hGH) were carried out in 6 children with small-for-dates dwarfism. Responses to insulin, glucose, glucagon and arginine as well as nitrogen balance studies were evaluated before and after the patients had been treated with hGH. On the basis of these responses the patients could be divided into three groups: I) Two patients grew when treated with hGH. They had significantly elevated maximal hGH levels following insulin administration (65 and 36 ng/ml), maximal immunoreactive insulin (IRI) levels were relatively low following arginine stimulation and blood sugar levels were less than 45 mg/100 ml 90 min after insulin administration; II) The one patient in this group did not grow at an accelerated rate when treated with hGH. The insulin-stimulated hGH level (49 ng/ml) was significantly elevated when compared to control values. Both basal and stimulated levels of IRI were also significantly greater than control levels. This patient was the only one who responded acutely to hGH treatment with an increase in sulfation factor (SF) concentration; and III) The remaining three patients did not increase growth rates when treated with hGH, had normal or high maximal hGH concentrations, normal IRI levels and normal SF and free fatty acid concentrations which were generally unresponsive to hGH. It is felt that these findings may offer insight into the mechanisms controlling mammalian growth.