Ghrelin in domestic animals: distribution in stomach and its possible role

Ghrelin, a novel growth-hormone-releasing acylated peptide, was recently is olated from rat and human stomachs. In rat, peripheral or central administr ation of ghrelin stimulates the secretion of growth hormone (GH) from the p ituitary gland. Recent work suggests that ghrelin plays an important role i n energy homeostasis, body weight, and food intake. We examined the distrib ution of cells immunoreactive to ghrelin in the stomachs of domestic animal s and rats, using a polyclonal antibody for the N-terminal fragment of rat ghrelin [1-11]. We measured the plasma levels of ghrelin before and after f eeding in cows, and GH levels after central administration of ghrelin in Sh iba goats, to elucidate the possible role of ghrelin. Immunostained cells w ere widely distributed from the neck to the base of the oxyntic gland in al l animals. The plasma ghrelin concentration in cows decreased significantly 1 It after feeding, and then recovered to pre-feeding levels. Administrati on of ghrelin into the third ventricle in Shiba goats dramatically increase d the plasma GH concentration dose-dependently. These results suggest that ghrelin plays an important role in GH secretion and feeding regulation in d omestic animals. (C) 2001 Elsevier Science Inc. All rights reserved.