Abstract:

Abstract:Objective  To examine the regulation of neuropeptide Y (NPY)  on sweet taste in the central nucleus of amygdala(CeA) and to explore its possible mechanism.Methods 58 male SD  rats were chosen,and 10  rats of them were divided into drinking saccharin solution group(n=5) and drinking distilled water group(n=5);after 2 h,the rat brain was obtained.The expressions of NPY and c-Fos in CeA were detected by immunohistochemical staining method.The other 48  rats were implanted cannula in CeA.The postoperative 24 rats were randomly divided into 4 groups,and the rats in 2 groups were injected with NPY and the rats in the other 2 groups were injected with  saline in CeA,and the intake of saccharin solution and distilled water were detected 2 h later.The other postoperative 24 rats were randomly divided into 4 groups,and the rats in 2 groups were intraperitoneally  injected with naloxone and the rats in the other 2 groups were intraperitoneally injected with saline,after 2 min,the rats were injected with NPY or saline in CeA,and the intake of saccharin solution were detected 2 h later.Results The NPY and c-Fos expressions in CeA were significantly increased after drinking saccharin solution (P<0.05).The intake of saccharin solution was significantly increased after injecting NPY in CeA(P<0.05);the pre-treatment of naloxone blocked the orexigenic effect of NPY(P<0.05).Conclusion NPY in CeA may play an important role in the regulation of sweet taste of saccharin solution,and the mechanism may be related to the opioid system.

Key words: neuropeptide Y;central nucleus of amygdala;c-Fos expression;sweet taste