This study was performed to investigate whether the blockade of cholinergic muscarinic and adrenergic pathways was involved in the GH- releasing effect of GH-releasing peptide-2 (GHRP-2) in ovariectomized ewes. Cholinergic muscarinic antagonist, atropine (0.2 mg/kg, iv, 15 min before GHRP-2 administration) blunted the GH secretion caused by GHRP-2 (12.5 μg/kgBW). α-Adrenergic antagonist phentolamine (15 μg/kgBW·min, infusion from -15 to 30 min) did not affect the GH response to GHRP-2, and β- adrenergic antagonist propranolol (0.25 mg/kgBW, iv, 15 min before GHRP-2 administration) did not suppress the GHRP-2-induced GH release. These results showed that cholinergic muscarinic antagonist agent, atropine, exerts an inhibitory effect on GHRP-2-induced GH secretion in ovariectomized ewes.
- Adrenergic receptor
- GH-releasing peptide-2 (GHRP-2)
- Muscarinic receptor
ASJC Scopus subject areas
- Endocrinology, Diabetes and Metabolism