目的:通过构建营养性肥胖雄性大鼠的模型,探讨下丘脑弓状核kisspeptin/kiss1r系统和促性腺激素释放激素(GnRH)的表达和作用,以及对下丘脑-垂体-睾丸轴(HPT)的影响。方法:孕14 d SD大鼠,其后代随机分为正常组和高能饲料组,构建营养性肥...目的:通过构建营养性肥胖雄性大鼠的模型,探讨下丘脑弓状核kisspeptin/kiss1r系统和促性腺激素释放激素(GnRH)的表达和作用,以及对下丘脑-垂体-睾丸轴(HPT)的影响。方法:孕14 d SD大鼠,其后代随机分为正常组和高能饲料组,构建营养性肥胖模型。将肥胖大鼠进一步分为对照组和实验组,实验组侧脑室注入kisspeptin。记录体重参数和内分泌激素的改变;免疫组化和Western印迹检测各组大鼠下丘脑弓状核中瘦素受体(LepR)、kisspeptin、kiss1r和GnRH的蛋白表达。qRT-PCR检测各组大鼠下丘脑弓状核GnRH mRNA的表达。结果:成功构建营养性肥胖大鼠,体重参数和内分泌激素改变明显。相比较正常组,对照组大鼠弓状核LepR、kisspeptin和GnRH表达减少,侧脑室注入kisspeptin后,实验组大鼠弓状核GnRH显著增加,血清LH和T水平显著升高,未见LepR和kiss1r的改变。结论:中枢注入kisspeptin可以显著改善由营养性肥胖引起的GnRH低表达,纠正HPT轴功能失调,进而改善生殖功能。展开更多
Background: Kisspeptin has been demonstrated to affect the attainment of puberty in multiple species, presumably through its actions on GnRH and LH. It has previously been found there is an increase in expression of h...Background: Kisspeptin has been demonstrated to affect the attainment of puberty in multiple species, presumably through its actions on GnRH and LH. It has previously been found there is an increase in expression of hypothalamic in the rat and the monkey coincident with puberty. Whether a similar phenomenon occurs in the pig remains to be determined. The objectives of the current experiments were to determine 1) Plasma concentrations of estradiol-17β;2) Anterior pituitary gland concentrations of LH, IGF-I, kisspeptin, and anterior pituitary gland expression of LH-β and GnRH receptor;3) Mediobasal hypothalamus expression of Kiss1 and concentrations of kisspeptin during the peripubertal period in the gilt. Methods: Two experiments were performed, each with 25 crossbred gilts (151 d, 105 kg). Gilts were relocated and exposed to a mature boar beginning on d 1 and continuing throughout the experiments to naturally induce puberty. Gilts that stood immobile within 24 hours of slaughter were considered to have attained puberty. Plasma samples were collected on d 1, 3, and 7 of the first experiment and d 2, 4, 6, and 8 of the second experiment. Gilts were slaughtered on d 7 (experiment 1) or d 8 (experiment 2), when mediobasal hypothalamus (MBH), anterior pituitary glands (AP), and blood were collected. Relative expression of MBH Kiss1 and β-actin and AP GnRH receptor, LH-β, was determined using real-time reverse transcriptase PCR. Fold changes in relative expression were determined using the Relative Expression Software Tool. Hypothalamic and AP content of kisspeptin were determined by RIA and differences were determined using the GLIMMIX procedure of SAS. Results: Relative expression of Kiss1 was increased (P = 0.005) 2.2 fold in the gilts that had attained puberty in the first experiment, however, those that had attained puberty in the second were not different (P > 0.05) from gilts that had not. Relative expression of GnRH receptor was not different (P > 0.05) between treatments in both experiments. Relative expression of LH-β tended to be decreased (P = 0.09) 0.80 fold in gilts that attained puberty in the first experiment but was not different (P > 0.05) in gilts that attained puberty in the second experiment. AP concentrations of LH were not different (P > 0.05) between treatments in the first experiment and were decreased (P = 0.01) in gilts that attained puberty in the second experiment. AP concentrations of kisspeptin were not different (P > 0.05) in the first experiment but were increased (P = 0.04) in gilts that had attained puberty in the second experiment. MBH concentrations of kisspeptin were increased (P = 0.03) in gilts that had attained puberty in the first experiment but were not different (P > 0.05) between treatments in the second experiment. Conclusions: These data further support the role that MBH expression of Kiss1 and concentrations of kisspeptin and AP concentrations of kisspeptin fluctuate during the peripubertal period and may play a role in the attainment of puberty in the gilt.展开更多
Objective To explore the potential function of nutrition on kisspeptin/kisspeptin receptor （kisslr） system in the arcuate nucleus （ARC） of male rats. Methods Pregnant rats were obtained and male pups were used to ...Objective To explore the potential function of nutrition on kisspeptin/kisspeptin receptor （kisslr） system in the arcuate nucleus （ARC） of male rats. Methods Pregnant rats were obtained and male pups were used to establish obesity model. Body parameters and blood samples were evaluated. Immunohistochemistry was used to determine the localizations and protein levels of kisspeptin, kisslr, and leptin receptor （LepR） immunoreactivity （IR） in ARC. QRT-PCR was used to determine kissl-, kisslr-, LepR-, and GnRH-mRNA levels. Results The establishment of obesity model was successful as body parameters and hormones levels changed noticeably. Kisspeptin-, kisslr-, and LepR-IR were detected and protein levels decreased significantly in high-fat-diets （HFD） rats than controls. The mRNA levels of kissl, LepR and GnRH significantly decreased in the ARC of HFD-fed rats. No difference was observed in kisslr mRNA levels between the two groups. Conclusion These data suggest that failure to increase GnRH levels with HFD may be associated with pubertal down-regulation of LepR and kisspeptin/kisslr system in the ARC of male rats.展开更多
文摘目的:通过构建营养性肥胖雄性大鼠的模型,探讨下丘脑弓状核kisspeptin/kiss1r系统和促性腺激素释放激素(GnRH)的表达和作用,以及对下丘脑-垂体-睾丸轴(HPT)的影响。方法:孕14 d SD大鼠,其后代随机分为正常组和高能饲料组,构建营养性肥胖模型。将肥胖大鼠进一步分为对照组和实验组,实验组侧脑室注入kisspeptin。记录体重参数和内分泌激素的改变;免疫组化和Western印迹检测各组大鼠下丘脑弓状核中瘦素受体(LepR)、kisspeptin、kiss1r和GnRH的蛋白表达。qRT-PCR检测各组大鼠下丘脑弓状核GnRH mRNA的表达。结果:成功构建营养性肥胖大鼠,体重参数和内分泌激素改变明显。相比较正常组,对照组大鼠弓状核LepR、kisspeptin和GnRH表达减少,侧脑室注入kisspeptin后,实验组大鼠弓状核GnRH显著增加,血清LH和T水平显著升高,未见LepR和kiss1r的改变。结论:中枢注入kisspeptin可以显著改善由营养性肥胖引起的GnRH低表达,纠正HPT轴功能失调,进而改善生殖功能。
文摘Background: Kisspeptin has been demonstrated to affect the attainment of puberty in multiple species, presumably through its actions on GnRH and LH. It has previously been found there is an increase in expression of hypothalamic in the rat and the monkey coincident with puberty. Whether a similar phenomenon occurs in the pig remains to be determined. The objectives of the current experiments were to determine 1) Plasma concentrations of estradiol-17β;2) Anterior pituitary gland concentrations of LH, IGF-I, kisspeptin, and anterior pituitary gland expression of LH-β and GnRH receptor;3) Mediobasal hypothalamus expression of Kiss1 and concentrations of kisspeptin during the peripubertal period in the gilt. Methods: Two experiments were performed, each with 25 crossbred gilts (151 d, 105 kg). Gilts were relocated and exposed to a mature boar beginning on d 1 and continuing throughout the experiments to naturally induce puberty. Gilts that stood immobile within 24 hours of slaughter were considered to have attained puberty. Plasma samples were collected on d 1, 3, and 7 of the first experiment and d 2, 4, 6, and 8 of the second experiment. Gilts were slaughtered on d 7 (experiment 1) or d 8 (experiment 2), when mediobasal hypothalamus (MBH), anterior pituitary glands (AP), and blood were collected. Relative expression of MBH Kiss1 and β-actin and AP GnRH receptor, LH-β, was determined using real-time reverse transcriptase PCR. Fold changes in relative expression were determined using the Relative Expression Software Tool. Hypothalamic and AP content of kisspeptin were determined by RIA and differences were determined using the GLIMMIX procedure of SAS. Results: Relative expression of Kiss1 was increased (P = 0.005) 2.2 fold in the gilts that had attained puberty in the first experiment, however, those that had attained puberty in the second were not different (P > 0.05) from gilts that had not. Relative expression of GnRH receptor was not different (P > 0.05) between treatments in both experiments. Relative expression of LH-β tended to be decreased (P = 0.09) 0.80 fold in gilts that attained puberty in the first experiment but was not different (P > 0.05) in gilts that attained puberty in the second experiment. AP concentrations of LH were not different (P > 0.05) between treatments in the first experiment and were decreased (P = 0.01) in gilts that attained puberty in the second experiment. AP concentrations of kisspeptin were not different (P > 0.05) in the first experiment but were increased (P = 0.04) in gilts that had attained puberty in the second experiment. MBH concentrations of kisspeptin were increased (P = 0.03) in gilts that had attained puberty in the first experiment but were not different (P > 0.05) between treatments in the second experiment. Conclusions: These data further support the role that MBH expression of Kiss1 and concentrations of kisspeptin and AP concentrations of kisspeptin fluctuate during the peripubertal period and may play a role in the attainment of puberty in the gilt.
基金supported by grants from the Natural Science Foundation of Shandong,Peoples’ Republic of China(ZR2012HM039)
文摘Objective To explore the potential function of nutrition on kisspeptin/kisspeptin receptor （kisslr） system in the arcuate nucleus （ARC） of male rats. Methods Pregnant rats were obtained and male pups were used to establish obesity model. Body parameters and blood samples were evaluated. Immunohistochemistry was used to determine the localizations and protein levels of kisspeptin, kisslr, and leptin receptor （LepR） immunoreactivity （IR） in ARC. QRT-PCR was used to determine kissl-, kisslr-, LepR-, and GnRH-mRNA levels. Results The establishment of obesity model was successful as body parameters and hormones levels changed noticeably. Kisspeptin-, kisslr-, and LepR-IR were detected and protein levels decreased significantly in high-fat-diets （HFD） rats than controls. The mRNA levels of kissl, LepR and GnRH significantly decreased in the ARC of HFD-fed rats. No difference was observed in kisslr mRNA levels between the two groups. Conclusion These data suggest that failure to increase GnRH levels with HFD may be associated with pubertal down-regulation of LepR and kisspeptin/kisslr system in the ARC of male rats.
