Bovolin Patrizia, Cottone Erika, Pomatto Valentina, Fasano Silvia, Pierantoni Riccardo, Cobellis Gilda, Meccariello Rosaria
Department of Life Sciences and Systems Biology, University of Turin , Turin , Italy ; Neuroscience Institute of Turin, University of Turin , Turin , Italy.
Department of Life Sciences and Systems Biology, University of Turin , Turin , Italy.
Front Endocrinol (Lausanne). 2014 Apr 15;5:54. doi: 10.3389/fendo.2014.00054. eCollection 2014.
Endocannabinoids (eCBs) are natural lipids regulating a large array of physiological functions and behaviors in vertebrates. The eCB system is highly conserved in evolution and comprises several specific receptors (type-1 and type-2 cannabinoid receptors), their endogenous ligands (e.g., anandamide and 2-arachidonoylglycerol), and a number of biosynthetic and degradative enzymes. In the last few years, eCBs have been described as critical signals in the control of male and female reproduction at multiple levels: centrally, by targeting hypothalamic gonadotropin-releasing-hormone-secreting neurons and pituitary, and locally, with direct effects on the gonads. These functions are supported by the extensive localization of cannabinoid receptors and eCB metabolic enzymes at different levels of the hypothalamic-pituitary-gonadal axis in mammals, as well as bonyfish and amphibians. In vivo and in vitro studies indicate that eCBs centrally regulate gonadal functions by modulating the gonadotropin-releasing hormone-gonadotropin-steroid network through direct and indirect mechanisms. Several proofs of local eCB regulation have been found in the testis and male genital tracts, since eCBs control Sertoli and Leydig cells activity, germ cell progression, as well as the acquisition of sperm functions. A comparative approach usually is a key step in the study of physiological events leading to the building of a general model. Thus, in this review, we summarize the action of eCBs at different levels of the male reproductive axis, with special emphasis, where appropriate, on data from non-mammalian vertebrates.
内源性大麻素（eCBs）是调节脊椎动物一系列生理功能和行为的天然脂质。eCB系统在进化过程中高度保守，包括几种特定的受体（1型和2型大麻素受体）、它们的内源性配体（如花生四烯乙醇胺和2-花生四烯酸甘油酯）以及一些生物合成和降解酶。在过去几年中，eCBs已被描述为在多个层面控制雄性和雌性生殖的关键信号：在中枢层面，通过作用于下丘脑分泌促性腺激素释放激素的神经元和垂体；在局部层面，直接作用于性腺。大麻素受体和eCB代谢酶在哺乳动物、硬骨鱼和两栖动物下丘脑-垂体-性腺轴的不同水平广泛定位，支持了这些功能。体内和体外研究表明，eCBs通过直接和间接机制调节促性腺激素释放激素-促性腺激素-类固醇网络，从而在中枢层面调节性腺功能。在睾丸和雄性生殖道中已发现了一些局部eCB调节的证据，因为eCBs控制支持细胞和间质细胞的活性、生殖细胞的发育进程以及精子功能的获得。比较研究方法通常是构建通用模型的生理事件研究中的关键步骤。因此，在本综述中，我们总结了eCBs在雄性生殖轴不同水平的作用，并在适当的地方特别强调了来自非哺乳动物脊椎动物的数据。
