Administration of motilin into the lateral hypothalamus increases gastric antrum motility and activates the dorsal vagal complex in rats / 生理学报

ABSTRACT

The effects of administration of motilin into the lateral hypothalamic area (LHA) on gastric antrum motility in conscious rats and on gastric distention (GD) sensitive neurons in dorsal vagal complex (DVC) in anesthetized rats were studied. Microinjection of motilin (0.37 nmol/0.5 microl) into the LHA increased the gastric antrum motility index by 76.29 +/- 4.09% (P<0.01). In 60 GD sensitive neurons, firing rate increased in 39 neurons (65%) and decreased in 21 neurons (35%), which were classified as GD-excitatory and GD-inhibitory neurons, respectively. Firing rate by 7.17 +/- 7.89% within 1.5 min in 15 of 24 GD-excitatory neurons, and firing rate increased by 44.35 +/- 7.89% in 12 of 14 GD-inhibitory neurons after motilin microinjection into the LHA. The results suggest that exogenous motilin in LHA plays a role in the regulation of gastric antrum motility possibly via the vagal pathway from LHA-DVC to the stomach.