Kereilwe Onalenna, Pandey Kiran, Borromeo Vitaliano, Kadokawa Hiroya
Faculty of Veterinary Medicine, Yamaguchi University, Yamaguchi-shi, Yamaguchi-ken 1677-1, Japan.
Dipartimento di Medicina Veterinaria, Università degli Studi di Milano, 26900, Italy.
Reprod Fertil Dev. 2018 Aug;30(9):1192-1203. doi: 10.1071/RD17377.
Preantral and small antral follicles may secret anti-Müllerian hormone (AMH) to control gonadotrophin secretion from ruminant gonadotrophs. The present study investigated whether the main receptor for AMH, AMH receptor type 2 (AMHR2), is expressed in gonadotrophs of postpubertal heifers to control gonadotrophin secretion. Expression of AMHR2 mRNA was detected in anterior pituitaries (APs) of postpubertal heifers using reverse transcription-polymerase chain reaction. An anti-AMHR2 chicken antibody was developed against the extracellular region near the N-terminus of bovine AMHR2. Western blotting using this antibody detected the expression of AMHR2 protein in APs. Immunofluorescence microscopy using the same antibody visualised colocalisation of AMHR2 with gonadotrophin-releasing hormone (GnRH) receptor on the plasma membrane of gonadotrophs. AP cells were cultured for 3.5 days and then treated with increasing concentrations (0, 1, 10, 100, or 1000pgmL-1) of AMH. AMH (10-1000pgmL-1) stimulated (P<0.05) basal FSH secretion. In addition, AMH (100-1000pgmL-1) weakly stimulated (P<0.05) basal LH secretion. AMH (100-1000pgmL-1) inhibited GnRH-induced FSH secretion, but not GnRH-induced LH secretion, in AP cells. In conclusion, AMHR2 is expressed in gonadotrophs of postpubertal heifers to control gonadotrophin secretion.
窦前卵泡和小窦卵泡可能分泌抗苗勒管激素（AMH），以控制反刍动物促性腺激素细胞分泌促性腺激素。本研究调查了AMH的主要受体，即2型AMH受体（AMHR2），是否在青春期后小母牛的促性腺激素细胞中表达，以控制促性腺激素的分泌。使用逆转录-聚合酶链反应在青春期后小母牛的垂体前叶（AP）中检测到AMHR2 mRNA的表达。针对牛AMHR2 N端附近的细胞外区域制备了一种抗AMHR2鸡抗体。使用该抗体进行的蛋白质免疫印迹检测到AP中AMHR2蛋白的表达。使用相同抗体的免疫荧光显微镜观察到AMHR2与促性腺激素释放激素（GnRH）受体在促性腺激素细胞质膜上的共定位。将AP细胞培养3.5天，然后用浓度递增（0、1、10、100或1000 pg/mL-1）的AMH处理。AMH（10-1000 pg/mL-1）刺激（P<0.05）基础FSH分泌。此外，AMH（100-1000 pg/mL-1）微弱刺激（P<0.05）基础LH分泌。在AP细胞中，AMH（100-1000 pg/mL-1）抑制GnRH诱导的FSH分泌，但不抑制GnRH诱导LH分泌。总之，AMHR2在青春期后小母牛的促性腺激素细胞中表达，以控制促性腺激素的分泌。
