Sympathoadrenal counterregulation in patients with hypothalamic craniopharyngioma

In humans, the role of hypothalamic centers for activation of counterregulatory release of catecholamines and glucagon during hypoglycemia is unclear. To address this question, we investigated the counterregulatory response to acute insulin-induced hypoglycemia of glucagon, epinephrine, and norepinephrine in eight patients who had undergone transcranial surgery for a craniopharyngioma extending to the hypothalamic region. We compared the patients’ responses with those of four patients suffering from hypopituitarism and of six healthy subjects. After the iv injection of 0.1 U of human insulin per kg of body weight in the patients or 0.15 U in healthy subjects, the plasma glucose concentrations decreased to similar minimum levels within 30 min in all three groups. All subjects recovered spontaneously from hypoglycemia within 2 h. In five of eight craniopharyngioma patients, only a small counterregulatory rise in plasma epinephrine (≤2-fold) and norepinephrine could be observed (P < 0.05 for epinephrine and ...