Krzymowski T
Division of Reproduction Endocrinology and Pathophysiology, Polish Academy of Sciences, Olsztyn.
J Physiol Pharmacol. 1992 Dec;43(4 Suppl 1):5-19.
With the inrush of new data the recent clear division of neural, hormonal and immunological regulation has been seriously complicated. Both central and peripheral neural tissue produce over 30 neuropeptides, among which are many classic peptide hormones. A steroid biosynthetic pathway has been demonstrated in oligodendrocytes. However, the distribution and role of peptydoergic neurons within the reproductive system are only superficially known among farm animals. Neurons have receptors for many hormones and interleukins. Cells of the immune system, in addition to secretion of many interleukins and interferons, produce neuropeptides locally and they possess specific receptors for them as well. Till now, the interaction between the nervous, hormonal and immunological systems has not been taken into account while investigating the functions of ovarian follicles, the corpus luteum, oviduct and uterus. The penetration of blood and lymphatic vessels by hormones, neuropeptides and cytokins has not been taken into consideration also. The counter current transfer of many steroid and peptide hormones from ovarian venous and lymphatic effluent to arterial blood supplying the ovary and through arterial anastomoses of the oviduct and uterus has been hithero shown. It has been demonstrated that thanks to this system, arterial blood supplying the uterus and oviduct has, in physiological conditions, a much higher level of some steroid hormones such as progesterone and androstendione, 37% and 36% respectively, than in systemic blood. Recently, a powerful exchange system for resupplying hormones to the brain which is dependent on the phase of the estrous cycle, has been discovered. It has also been demonstrated that neuropeptides LH-RH, beta-endorphin and oxytocin as well as the steroid hormone progesterone, were counter current transferred from venous to arterial blood at the perihypophyseal cavernous sinus and carotid rete in sheep and gilts, but only during specific periods of reproductive activity. The mechanism of this process is still unknown. The role of peptydoergic neurons and cytokins in vascular permeability during hormone counter current transfer in the broad ligament vasculature, perihypophyseal cavernous sinus and carotid rete has not been investigated. It is suggested that progress in this area may change our point of view on many basic regulatory mechanisms involved in animal reproductive physiology.
随着新数据的涌入，神经、激素和免疫调节之间最近明确的划分变得极为复杂。中枢和外周神经组织都能产生30多种神经肽，其中有许多是经典的肽类激素。在少突胶质细胞中已证实存在类固醇生物合成途径。然而，在农场动物中，肽能神经元在生殖系统中的分布和作用仅为初步了解。神经元具有许多激素和白细胞介素的受体。免疫系统的细胞除了分泌多种白细胞介素和干扰素外，还能在局部产生神经肽，并且它们也拥有针对这些神经肽的特异性受体。到目前为止，在研究卵巢卵泡、黄体、输卵管和子宫的功能时，尚未考虑神经、激素和免疫系统之间的相互作用。激素、神经肽和细胞因子在血管和淋巴管中的渗透情况也未被考虑。此前已表明，许多类固醇和肽类激素可通过逆流从卵巢静脉和淋巴流出液转移至供应卵巢的动脉血，并通过输卵管和子宫的动脉吻合支进行转移。已经证明，借助该系统，在生理条件下，供应子宫和输卵管的动脉血中某些类固醇激素，如孕酮和雄烯二酮的水平分别比全身血液中高37%和36%。最近，发现了一个强大的依赖发情周期阶段的向大脑重新供应激素的交换系统。还已证明，神经肽促黄体生成素释放激素（LH-RH）、β-内啡肽和催产素以及类固醇激素孕酮，在绵羊和后备母猪的垂体周围海绵窦和颈动脉网处，仅在生殖活动的特定时期从静脉血逆流转移至动脉血。该过程的机制仍然未知。在阔韧带脉管系统、垂体周围海绵窦和颈动脉网中，激素逆流转移过程中肽能神经元和细胞因子对血管通透性的作用尚未得到研究。有人认为，这一领域的进展可能会改变我们对动物生殖生理学中许多基本调节机制的看法。
