The Composition Of The Hippocampal-hypothalamic Arcuate Nucleus Ghrelin Neural Pathway And Its Effect On Gastric Motility

Objective:(1)To explore the composition of the neural pathways of hippocampal CA1and the hypothalamic Arc nucleus ghrelin;(2) of ghrelin in the hippocampal CA1region-under the influence and mechanism of the hypothalamic Arc nucleus pathway regulating gastric motility.Method:(1) Fluorogold (FG) retrograde tracing experiments to observe the composition of the neural pathways in the hypothalamic arcuate nucleus and hippocampus, combined with fluorescence immunohistochemistry observed ghrelin neurons in the hippocampal CA1region-hypothalamic arcuate nucleusbetween the projection.(2) the hippocampal CA1region respectively, microinjection of ghrelin and ghrelin receptor antagonist D-Lys3-GHRP-6, freely moving rats gastric motility.(3) electrical damage to the hypothalamic arcuate nucleus observed in hippocampal CA1microinjection of ghrelin on gastric motility of freely moving rats.Results:(1)The retrograde tracing combined with immunofluorescence staining studies have shown that the hippocampus and the arcuate nucleus were injected with FG,7days after the visible arcuate nucleus, a large number of marked FG neurons in the hippocampus, combined with ghrelin antiserum immunohistochemistry, can be seen inArc, hippocampus FG labeled neurons in the expression of ghrelin-immunoreactive material.(2) in the body of gastric motility and CA1, respectively, micro-injection of ghrelin in the arcuate nucleus, can significantly enhance the awake rat gastric motility (P<0.01), the role of the ghrelin receptor blocking agent D-Lys3-GHRP-6blocked (P>0.05); electrical damage to the arcuate nucleus of the hypothalamus, gastric motility compared with control group no significant difference (P>0.05), followed by the hippocampal injection of ghrelin in rats to promote gastric motility in the role of damage to the arcuate nucleus+hippocampal injection of ghrelin group than in the sham significantly reduced (P<0.01), but electrical damage to the arcuate nucleus+hippocampal NS group, gastric motility was significantly increased (P<0.05-0.01)。 Conclusion:Our results suggest that Ghrelin neural pathway between the hippocampus and the arcuate nucleus. Hippocampus maybe promotes gastric motilinty by activating its receptors. Hippocampus-the arcuate nucleus pathway is involved in the regulation of ghrelin on gastric motility.