Jiménez-Trejo Francisco, Coronado-Mares Isabel, Arriaga-Canon Cristian, Herrera Luis A, Roque-Ramírez Bladimir, Chávez-Saldaña Margarita, Rojas-Castañeda Julio, Cerbón Marco, Vigueras-Villaseñor Rosa M
Instituto Nacional de Pediatría, Ciudad de México, Mexico.
Facultad de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, Ciudad de México, Mexico.
Front Neuroanat. 2021 Feb 19;14:570058. doi: 10.3389/fnana.2020.570058. eCollection 2020.
Serotonin (5-HT) is member of a family of indolamine molecules that participate in a wide variety of biological processes. Despite its important role in the regulation of local blood systems, little is known about the physiological function of 5-HT in reproductive organs, its functional implications, and its role in the reproduction of mammals. In the present work, we evaluated the localization and distribution of 5-HT (using histochemical analysis of indolamines) and different components of the serotoninergic system in rat testes. We detected local synthesis and degradation through immunofluorescence and western blot analyses against the TPH1, MAO, 5-HT, and VMAT1 serotonin transporters. We also identified the localization and distribution of the 5-HT, 5-HT, and 5-HT receptors. RT-PCR results showed the presence of the Tph1, Maoa, Slc6a4, and Htr3a genes in testes and in the brain stem (Tph1 was used as a negative control). High-performance liquid chromatography was used to determine the presence of 5-HT and the activity of tryptophan hydroxylase in testes homogenates . Our observations suggest that TPH1 activity and local 5-HT synthesis befall in rat testes. We propose that 5-HT could participate in the regulation of testosterone synthesis and in the spermatogenesis process via local serotoninergic system. However, more studies are needed before concluding that rat testes, or those of other mammals, contain an active form of tryptophan hydroxylase and produce 5-HT.
血清素（5-羟色胺，5-HT）是吲哚胺分子家族的一员，参与多种生物过程。尽管其在局部血液系统调节中具有重要作用，但关于5-HT在生殖器官中的生理功能、其功能意义以及在哺乳动物生殖中的作用，人们了解甚少。在本研究中，我们评估了5-HT（使用吲哚胺的组织化学分析）和血清素能系统的不同成分在大鼠睾丸中的定位和分布。我们通过针对色氨酸羟化酶1（TPH1）、单胺氧化酶（MAO）、5-HT和囊泡单胺转运体1（VMAT1）血清素转运体的免疫荧光和蛋白质印迹分析检测了局部合成和降解。我们还确定了5-HT受体、5-HT受体和5-HT受体的定位和分布。逆转录聚合酶链反应（RT-PCR）结果显示，睾丸和脑干中存在Tph1、Maoa、Slc6a4和Htr3a基因（Tph1用作阴性对照）。采用高效液相色谱法测定睾丸匀浆中5-HT的存在及色氨酸羟化酶的活性。我们的观察结果表明，TPH1活性和局部5-HT合成发生在大鼠睾丸中。我们提出，5-HT可能通过局部血清素能系统参与睾酮合成的调节和精子发生过程。然而，在得出大鼠睾丸或其他哺乳动物睾丸含有活性形式的色氨酸羟化酶并产生5-HT的结论之前，还需要更多的研究。
