Abstract
The effect of testosterone on plasma growth hormone response to hypoglycemia was studied in 4 patients with anorchia, in a patient with delayed puberty, and in a patient with panhypopituitarism. Insulin tolerance tests were performed a) without testosterone therapy, b) 2 days after a single injection of testosterone, and c) in 3 patients after 2–3 months of full replacement therapy. Testosterone led to an increased release of growth hormone in all 4 patients with anorchia and in the boy with delayed puberty. This increase appeared 2 days after a single injection of testosterone; it became still higher after 2–3 months of full replacement therapy. In the patient with panhypopituitarism, no growth hormone response was observed. The normalization of growth hormone release after one injection of testosterone might be helpful to exclude isolated growth hormone deficiency in boys with delayed puberty and small stature who present a doubtful growth hormone response to hypoglycemia.