Infusion of epinephrine inhibited growth hormone (GH) and insulin responses of intact
sheep to arginine (0.5 gm/kg). Chronic exposure to the α-adrenergic receptor blocker
phentolamine prevented the epinephrine inhibition of insulin release but a similar
treatment with propranolol, a β-adrenergic blocking drug was ineffective. Neither
phentolamine nor propranolol could counteract the inhibitory effect of epinephrine
on GH secretion. It is suggested that the mechanisms mediating the effects of catecholamines
on GH release and insulin secretion are different.
Growth Hormone Secretion - Insulin Secretion - Arginine - Epinephrine - Phentolamine
- Propranolol
