.1, The Role Of Motilin Receptor Agonist Erythromycin On Gastric Motility, Cerebellar Purkinje Cells, Ghrelin In The Role Of Lateral Hypothalamic Glucose-sensitive Nerves In Activity,

Background Motilin, a 22-amino acid residue gastrointestinal peptide, is released by the endocrine cells in the mucosa of the upper part of the small intestine. The peripheral function of motilin mainly involved the regulation of the migrating motor complex (MMC)-phase III of the gastrointestinal tract in interdigestive state. Early more than twenty years ago, the motilin-like immunoreactivity was found in the central nervous system (CNS), and the following studies and researches indicated that motilin may have various central effects, including the regulation of feeding and drinking behaviour, central and brainstem neuronal modulation, pituitary hormone secretion, and reducing the levels of anxiety in mice. In recent years our laboratory focused on the effect of motilin on the gastric motility in rats and its mechanism. We have already observed that microinjection of motilin in several regions of the brain can stimulate gastric motor activity in conscious rats.Object To study Central mechanism mediating the effects of EM on gastric motolity in diabetic mellitus rats.Methods The administration erythromycin(EM) of intracerebroventricle microinjection (i.c.v.) and recording of gastric motility in conscious diabetic rats have been used.Results The i.c.v. of EM can increase the amplitude of gastric motility.EM 50u g in 5 min (50.13±31.35)% (P<0.05) ;EM 100u g in 5 min is(174.82±119.10)%, in 10 min(184.38 ±158.89)%,and in 15 min (58.62 ±64.96)%(P<0.05);Also the administration of i.c.v of EM can increase the frequence of gastric motility, EM 50 u g in 5 min (25.13±18.27)% ( P<0.05) ; EM 100 n gin5minis(70.43±61.68)%, in 10 min (123.15± 143.12)%, and in 15 min (70.53± 61.68)% (P<0.05) . The adminisration of i.c.v of EM 50u g^ EM 100u g have the dose-dependent increases on the amplitude of gastric motility,but the frequence does not . The i.c.v. of GM-109 2 u g can block the effect of EM.Conclusion the central administration EM to enhance gastric motility may be mediated by the central motilin receptor.