Dipartimento di Medicina Veterinaria, Università di Perugia, 06126, Perugia, PG, Italy; Scuola di Bioscienze e Medicina Veterinaria, Università di Camerino, 62032, Camerino, MC, Italy.
Dipartimento di Medicina Veterinaria, Università di Perugia, 06126, Perugia, PG, Italy.
Theriogenology. 2020 Aug;152:1-7. doi: 10.1016/j.theriogenology.2020.04.006. Epub 2020 Apr 15.
The objectives of this study were to evaluate in horse testes the expression of kisspeptin (KiSS) and GnRH1 neuropeptides and their cognate receptors, KiSS1R and GnRH1R, as well as their action on testosterone, GnRH1, prostaglandin F2α (PGF2α), and PGE2 synthesis and cyclooxygenase 1 (COX1) and COX2 activity by Leydig cells in vitro. Testes were obtained from 9 sexually mature horses by surgical castration. Immunohistochemistry, evidenced the presence of KiSS, KiSS1R, GnRH, and GnRH1R in Leydig cells, whereas germinal and Sertoli cells were positive only for GnRH1. Transcripts for both neuropeptides and their cognate receptors were revealed in isolated Leydig cells by RT-PCR. Isolated and purified Leydig cells were in vitro cultured with agonists and antagonists of KiSS (KiSS-10 and KiSS-234, respectively) and GnRH1 (buserelin and antide, respectively). KiSS-10 and buserelin increased (P < 0.01) COX1 activity and testosterone and PGF2α basal secretion, while decreased (P < 0.01) that of PGE2. KiSS-10 and buserelin did not affect COX2 activity. GnRH1 basal production was increased (P < 0.01) by KiSS-10, but not by buserelin. Antide counteracted the KiSS and GnRH1 effects, whereas KiSS-234 influence only those of KiSS. Summarizing, the KiSS/GnRH1 system is present in horse Leydig cells and modulates their endocrine activity. In particular, the endocrine effects of KiSS are mediated by GnRH1, so suggesting that hypothalamic-like interaction between KiSS and GnRH1 occurs also in Leydig cells.
本研究旨在评估在马睾丸中 kisspeptin (KiSS) 和 GnRH1 神经肽及其同源受体 Kiss1R 和 GnRH1R 的表达，以及它们对睾酮、GnRH1、前列腺素 F2α (PGF2α) 和 PGE2 合成以及细胞色素 P450 1 (COX1) 和 COX2 活性的影响。通过手术去势从 9 只性成熟马获得睾丸。免疫组织化学显示 KiSS、KiSS1R、GnRH 和 GnRH1R 存在于 Leydig 细胞中，而生殖细胞和 Sertoli 细胞仅对 GnRH1 呈阳性。通过 RT-PCR 揭示了两种神经肽及其同源受体在分离的 Leydig 细胞中的转录本。用 KiSS（KiSS-10 和 KiSS-234）和 GnRH1（buserelin 和 antide）的激动剂和拮抗剂在体外培养分离和纯化的 Leydig 细胞。KiSS-10 和 buserelin 增加（P < 0.01）COX1 活性和基础睾酮和 PGF2α 的分泌，同时降低（P < 0.01）PGE2 的分泌。KiSS-10 和 buserelin 不影响 COX2 活性。KiSS-10 增加（P < 0.01）基础 GnRH1 的产生，但 buserelin 没有。Antide 拮抗 KiSS 和 GnRH1 的作用，而 KiSS-234 仅影响 KiSS 的作用。综上所述，KiSS/GnRH1 系统存在于马 Leydig 细胞中，并调节其内分泌活性。特别是，KiSS 的内分泌作用是通过 GnRH1 介导的，因此表明 KiSS 和 GnRH1 之间也存在类似下丘脑的相互作用。
