Galanin-induced growth hormone secretion in conscious rats: evidence for a possible involvement of somatostatin

Intracerebroventricular administration of galanin (GAL) potently evoked growth hormone (GH) secretion in conscious male rats. Pretreatments with neostigmine and cysteamine blunted the GAL-induced GH secretion. Pretreatment of animals with a specific anti-somatostatin serum significantly inhibited the GAL-induced GH secretion. On the contrary, GH-releasing hormone-induced GH secretion was significantly enhanced with cysteamine and anti-somatostatin serum. These results suggest that somatostatin is involved in GAL-induced GH secretion in rats.