Jafarpour Arsalan, Dehghani Faramarz, Korf Horst-Werner
Dr. Senckenbergische Anatomie, Institut der Anatomie II, Johann Wolfgang Goethe-Universität, Theodor-Stern-Kai 7, Haus 26/EG, 60590, Frankfurt am Main, Germany.
Department für Neurologie, Klinik für Schlafmedizin und Neuromuskuläre Erkrankungen, Universitätsklinikum Münster, Albert-Schweitzer-Campus 1, Gebäude A1, 48149, Münster, Germany.
Cell Tissue Res. 2017 Apr;368(1):115-123. doi: 10.1007/s00441-016-2544-1. Epub 2016 Dec 20.
Endocannabinoids (ECs) are ubiquitous endogenous lipid derivatives and play an important role in intercellular communication either in an autocrine/paracrine or in an endocrine fashion. Recently, an intrinsic EC system has been discovered in the hypophysial pars tuberalis (PT) of hamsters and humans. In hamsters, this EC system is under photoperiodic control and appears to influence the secretion of hormones such as prolactin from the adenohypophysis. We investigate the EC system in the PT of the rat, a frequently used species in endocrine research. By means of immunocytochemistry, enzymes involved in EC biosynthesis, e.g., N-arachidonoyl-phosphatidylethanolamine-phospholipase D (NAPE-PLD) and diacylglycerol lipase α (DAGLα) and enzymes involved in EC degradation, e.g., fatty acid amide hydrolase (FAAH) and cyclooxygenase-2 (COX-2), were demonstrated in PT cells of the rat. Immunoreactions (IR) for FAAH and for the cannabinoid receptor CB were observed in corticotrope cells of the rat adenohypophysis; these cells were identified by antibodies against proopiomelanocortin (POMC) or adrenocorticotrophic hormone (ACTH). In the outer zone of the median eminence, numerous nerve fibers and terminals displayed CB IR. The majority of these were also immunolabeled by an antibody against corticotropin-releasing factor (CRF). These results suggest that the EC system at the hypothalamo-hypophysial interface affects both the CRF-containing nerve fibers and the corticotrope cells in the adenohypophysis. Our data give rise to the hypothesis that, in addition to its well-known role in the reproductive axis, the PT might influence adrenal functions and, thus, the stress response and immune system.
内源性大麻素（ECs）是普遍存在的内源性脂质衍生物，在细胞间通讯中以自分泌/旁分泌或内分泌方式发挥重要作用。最近，在仓鼠和人类的垂体结节部（PT）中发现了一个内在的EC系统。在仓鼠中，这个EC系统受光周期控制，似乎会影响腺垂体中催乳素等激素的分泌。我们研究了大鼠PT中的EC系统，大鼠是内分泌研究中常用的物种。通过免疫细胞化学方法，在大鼠PT细胞中证实了参与EC生物合成的酶，如N-花生四烯酰磷脂酰乙醇胺磷脂酶D（NAPE-PLD）和二酰甘油脂肪酶α（DAGLα），以及参与EC降解的酶，如脂肪酸酰胺水解酶（FAAH）和环氧化酶-2（COX-2）。在大鼠腺垂体的促肾上腺皮质激素细胞中观察到FAAH和大麻素受体CB的免疫反应（IR）；这些细胞通过抗阿黑皮素原（POMC）或促肾上腺皮质激素（ACTH）的抗体进行鉴定。在正中隆起的外侧区，许多神经纤维和终末显示出CB IR。其中大多数也被抗促肾上腺皮质激素释放因子（CRF）的抗体免疫标记。这些结果表明，下丘脑-垂体界面的EC系统会影响含CRF的神经纤维和腺垂体中的促肾上腺皮质激素细胞。我们的数据提出了一个假设，即除了其在生殖轴中众所周知的作用外，PT可能会影响肾上腺功能，从而影响应激反应和免疫系统。
