Effects of Stress on Appetite in Rats Through Hypothalamus and Stomach Ghrelin Pathway

doi:10.12300/j.issn.1674-5817.2020.160

Abstract

Abstract: Objective To study the molecular mechanism of stress on appetite through hypothalamus and stomach ghrelin pathway. Methods Thirty-two male Wistar rats were randomly divided into a control group and a stress group with 16 rats in each group and 2 rats in each cage. Stress was induced by tail pinch for consecutive 21 days. Food intake and body weight of the rats in each group were recorded. Serum ghrelin concentrations of eight rats in each group were detected by ELISA on day 7 and day 21. Ghrelin protein expression in stomach and hypothalamus as well as Amp-activated protein kinase α2 (AMPKα2) protein expression in hypothalamus of rats were measured by Western blotting. The mRNA levels of ghrelin, growth hormone secretagogue receptor (GHSR) and leptin in stomach as well as ghrelin, AMPKa2, neuropeptide Y (NPY), agouti-related protein (AgRP) in hypothalamus were measured by real-time quantitative PCR. Results On day 7, the total food intake of rats in each cage in the stress group was higher than that in the control group (P < 0.05), and there was no significant difference in total food intake between the two groups on day 21 (P > 0.05). On day 7 and day 21, there was no significant difference in body weight between the two groups (P > 0.05). Stress upregulated the serum levels of acylated ghrelin (P < 0.01), the ghrelin protein expression levels in stomach and hypothalamus (P < 0.05), and the AMPKα2 protein expression level in hypothalamus (P < 0.01). Stress also upregulated the ghrelin and GHSR mRNA expression levels in stomach (P < 0.01), downregulated the leptin mRNA expression level in stomach (P < 0.01), and upregulated the ghrelin, AMPKα2, NPY and AgRP mRNA expression levels in hypothalamus (P < 0.01). Conclusion Tail pinch-induced stress can increase central and peripheral ghrelin levels in rats, and act as a temporary appetite enhancer.

Key words: Stress, Appetite, Ghrelin, Rats

CLC Number:

Q95-33
R-332

ZHAO Yiling, GAO Pengfei, XIAO Qian, ZHANG Lan, PAN Danqing, XU Yuemei. Effects of Stress on Appetite in Rats Through Hypothalamus and Stomach Ghrelin Pathway[J]. Laboratory Animal and Comparative Medicine, 2021, 41(3): 207-214.

Figures/Tables 5

References

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