The Lateral Septal Nuclei Ghrelin On Rat Gastric Motion Regulation And Mechanism Research

Objective:To investigate the effect of ghrelin in lateral septal nucleus on gastric motility in rats, and to explore its underlying mechanism in central nervous system.Methods:Ghrelin was microinjected into lateral septal nucleus and the gastric motility were measured by transducer and electrode embedmented into the stomach in conscious rats.Results:â‘ In the ghrelin group, after the lateral septal nucleus was administrated 20 nmol,200 nmol or 2000 nmol ghrelin for 6 minutes respectively, the amplitude (P<0.05-0.01) and frequency (P<0.05-0.01) of the gastric motility was significantly increased. And it was dose-dependently increased. Compared with the group of 200 nmol ghrelin+NS, the effect of ghrelin on promoting gastric motility including the amplitudes (P<0.05-0.01) and frequency (P<0.05) significantly disappeared after ghrelin+ D-Lys3-GHRP-6 mixture was injected into the lateral septal nucleus. However, there was no significant change for gastric motility while administration of ghrelin receptor antagonist D-Lys3-GHRP-6 alone (P>0.05).â‘¡The lateral septal nucleus injection of ghrelin 200 nmol ghrelin can significantly induce the expression of c-Fos protein in DVC (P<0.01).â‘¢The gastric motility amplitude (P<0.05) and frequency (P<0.05) were significantly decreased after subdiaphragmatic vagotomy. Comparing with the sham control group, the amplitude (P<0.05-0.01) and frequency (P<0.05) of gastric motility were significantly reduced by microinjection of ghrelin into lateral septal nucleus in subdiaphragmatic vagotomy rats. However, there was no significant change for amplitude (P>0.05) and frequency (P>0.05) of gastric motility comparing with the NS group.Conclusion:Exogenous ghrelin in lateral septal nucleus can regulate the gastric motility, and enhance the gastric motility significantly in conscious rats. This enhancement may participate via GHS-R by activating the lateral septal nucleus-DVC-vagus axis pathway.