Gupta M, Dangi S S, Chouhan V S, Hyder I, Babitha V, Yadav V P, Khan F A, Sonwane A, Singh G, Das G K, Mitra A, Bag S, Sarkar M
Division of Physiology and Climatology, Indian Veterinary Research Institute, Izatnagar 243122, India.
Department of Animal Sciences, University of Florida, Gainesville, FL 32611; D.H. Barron Reproductive and Perinatal Biology Research Program, University of Florida, Gainesville, FL 32611.
Domest Anim Endocrinol. 2014 Jul;48:21-32. doi: 10.1016/j.domaniend.2014.01.004. Epub 2014 Jan 21.
Evidence obtained during recent years provided has insight into the regulation of corpus luteum (CL) development, function, and regression by locally produced ghrelin. The present study was carried out to evaluate the expression and localization of ghrelin and its receptor (GHS-R1a) in bubaline CL during different stages of the estrous cycle and investigate the role of ghrelin on progesterone (P4) production along with messenger RNA (mRNA) expression of P4 synthesis intermediates. The mRNA and protein expression of ghrelin and GHS-R1a was significantly greater in mid- and late luteal phases. Both factors were localized in luteal cells, exclusively in the cytoplasm. Immunoreactivity of ghrelin and GHS-R1a was greater during mid- and late luteal phases. Luteal cells were cultured in vitro and treated with ghrelin each at 1, 10, and 100 ng/mL concentrations for 48 h after obtaining 75% to 80% confluence. At a dose of 1 ng/mL, there was no significant difference in P4 secretion between control and treatment group. At 10 and 100 ng/mL, there was a decrease (P < 0.05) in P4 concentration, cytochrome P45011A1 (CYP11A1), and 3-beta-hydroxysteroid dehydrogenase mRNA expression and localization. There was no difference in mRNA expression of steroidogenic acute regulatory protein between control and treatment group. In summary, the present study provided evidence that ghrelin and its receptor are expressed in bubaline CL and are localized exclusively in the cell cytoplasm and ghrelin has an inhibitory effect on P4 production in buffalo.
近年来获得的证据为局部产生的胃饥饿素对黄体（CL）发育、功能和退化的调节提供了深入了解。本研究旨在评估发情周期不同阶段水牛黄体中胃饥饿素及其受体（GHS-R1a）的表达和定位，并研究胃饥饿素对孕酮（P4）产生以及P4合成中间体信使核糖核酸（mRNA）表达的作用。胃饥饿素和GHS-R1a的mRNA和蛋白表达在黄体中期和后期显著更高。这两种因子均定位于黄体细胞，仅在细胞质中。胃饥饿素和GHS-R1a的免疫反应性在黄体中期和后期更强。在体外培养黄体细胞，在达到75%至80%汇合度后，分别用浓度为1、10和100 ng/mL的胃饥饿素处理48小时。在1 ng/mL剂量下，对照组和处理组之间的P4分泌没有显著差异。在10和100 ng/mL时，P4浓度、细胞色素P45011A1（CYP11A1）和3-β-羟基类固醇脱氢酶mRNA表达及定位均下降（P<0.05）。对照组和处理组之间类固醇生成急性调节蛋白的mRNA表达没有差异。总之，本研究提供的证据表明，胃饥饿素及其受体在水牛黄体中表达，且仅定位于细胞质中，胃饥饿素对水牛的P4产生具有抑制作用。
