Prolactin acts in the pathway of photoperiod regulating the reproduction of the Striped Hamsters

Abstract To study the effects of prolactin (PRL) in pituitary on the reproduction of the Striped Hamsters via the photoperiods. Mature female striped hamsters were raised under various photoperiods to study the differential expression pattern of PRL in pituitary, and prolactin receptor (PRLR) in the hypothalamus, pituitary and ovary. Photoperiods affect the pituitary PRL mRNA level and pituitary, hypothalamus and ovaries PRLR mRNA levels in striped hamsters. Positive correlations of PRL mRNA expression in the pituitary with that of PRLR in hypothalamus and ovaries, and that of GnRH in hypothalamus were determined. The serum concentration of PRL, FSH, LH and GnRH were significantly different among the striped hamsters from different photoperiods. Serum concentration of PRL is positively correlated with that of FSH, LH and GnRH of the striped hamsters. Photoperiod was important environment factor modulating the expression profile of PRL and PRLR in the striped hamsters.

摘要 本研究旨在探讨垂体催乳素（prolactin, PRL）通过光周期途径对黑线仓鼠（Striped Hamsters）繁殖功能的影响。研究人员将成熟雌性黑线仓鼠饲养于不同光周期环境中，以分析垂体中PRL以及下丘脑、垂体与卵巢内催乳素受体（prolactin receptor, PRLR）的差异表达模式。结果显示，光周期可显著影响黑线仓鼠垂体PRL信使核糖核酸（mRNA）的表达水平，以及下丘脑、垂体与卵巢中PRLR mRNA的表达水平。经检测，垂体PRL mRNA的表达量与下丘脑、卵巢中PRLR mRNA的表达量，以及下丘脑中促性腺激素释放激素（Gonadotropin-Releasing Hormone, GnRH）的表达量均呈显著正相关。不同光周期组的黑线仓鼠血清中PRL、卵泡刺激素（Follicle-Stimulating Hormone, FSH）、黄体生成素（Luteinizing Hormone, LH）及GnRH的浓度均存在显著差异。黑线仓鼠血清PRL浓度与血清FSH、LH及GnRH浓度呈显著正相关。综上，光周期是调控黑线仓鼠体内PRL与PRLR表达谱的重要环境因子。