[The relationships among raphe magnus nucleus, locus coeruleus and dorsal motor nucleus of vagus in the descending regulation of gastric motility].

Objective: To explore the interrelationship among dorsal motor nucleus of the vagus(DMV),locus coeruleus(LC) and raphe magnus nucleus(NRM) in the mechanism of the descending regulation on gastric motility,which may constitute a parasympathetic local circuit,work as a neural center of gastric modulation in brainstem.Methods: Using nucleus location,electric stimulation and lesion,together with microinjection,and recording the inter-gastric pressure.Results: ①LC stimulation could inhibit the gastric motility significantly(P0.01),DMV lesion weaken this effect,while blocking the α receptor on DMV could reverse the effect.②NRM stimulation reduced the amplitude of gastric constriction(P0.01),DMV lesion could abolish the effect,but blocking the 5-HT2A receptor on DMV depressed the gastric motility heavily(P0.01) like NRM stimulation.While LC lesion could abolish the effect of NRM stimulation,and microinjection of ritanserin into LC could likewise abolish it.Conclusion: ①LC inhibit the gastric motility via α receptor in DMV,and meanwhile may excite it through 5-HT2A receptor in DMV,these two ways work together to keeping the gastric motility amplitude normally.②NRM inhibit the gastric motility via 5-HT2A receptor in LC.