Human growth hormone response to pyridostigmine in normal and hGH deficient adolescents

There is evidence indicating that the cholinergic system positively modulates HGH secretion. In the present study, we observed the effects of cholinergic enhancement by pyridostigmine （PD）, a cholinesterase inhibitor, on hGH release in both normal （n=13） and hGH deficient （n=10） adolescents. Responses of hGH to insulin hypoglycemia （Ins） were also observed. In normal subjects, PD-induced serum hGH peak levels were significantly higher than that induced by Ins （P＜0.01）. By contrast, the hGH level in the patients with pituitary dwarfism showed no increase by both" tests. The study indicates that PD test may be considered a useful dyanamic test in evaluating pituitary function of hGH secretion in children and adolescents.