Mechanism Of Leptin On Impaired Ovarian Reserve Function After Cold Exposure In Female Rats 

Abstract

Previous studies have shown that cold exposure can cause disturbance of estrus cycle in female rats. However, whether cold exposure can cause organic pathological damage to the reproductive system of female rats was undefined. Meanwhile there are few reports on the mechanism of decompensation in rat reproductive function after cold exposure. This study aims to further discuss how cold exposure impact female ovarian reserve function in rats. Female rats were randomly divided into control group and cold exposure group. Ovarian reserve function, differential genes in hypothalamus reproductive regulation center or peripheral were evaluated. After cold exposure, ovarian reserve function was impaired, follicle development was abnormal, the number of mature follicles decreased significantly, the key hypothalamic reproductive regulation molecule GnRH decreased significantly, the response of its regulatory receptor NPY-5R was down-regulated, and the peripheral hormone serum leptin, which is closely related to it, decreased significantly. Our results indicate that cold exposure can lead to impaired ovarian function in female rats, resulting from decrease in serum leptin cause by WAT leptin depletion, which can release the inhibitory of NPY in the hypothalamus, and further lead to the down-regulation of GnRH expression, resulting in the whole HPO axis.