Wiltbank M C
Dept. of Dairy Sci., Univ. of Wisconsin-Madison 53706.
J Anim Sci. 1994 Jul;72(7):1873-83. doi: 10.2527/1994.7271873x.
This article reviews literature on the highly differentiated nature of the luteal cell types and their regulation in the mid-cycle corpus luteum of ruminants. The blood vessels of the corpus luteum are composed primarily of endothelial cells with few intraluteal arterioles or arteries. Blood flow to the corpus luteum does not seem to be regulated by tropic hormones, metabolic activity, or autonomic nerves, but it is dependent on maintenance of high blood pressure. The density of luteal capillaries and lack of luteal arterioles allows an elevated, relatively unregulated luteal blood flow. Steroidogenesis in the ruminant corpus luteum manifests both dependence on and independence from the actions of LH. Initial luteinization, growth, and development of the corpus luteum is dependent on LH action, but progesterone production by the mid-cycle corpus luteum of ruminants is relatively independent of acute LH stimulation. This apparent enigma may be due to distinct functional properties of the steroidogenic cell types in the corpus luteum. Progesterone production by the large luteal cells is relatively independent of LH action, but the small luteal cells respond to LH stimulation. Much of the progesterone produced by the mid-cycle corpus luteum is produced by the large luteal cells and may not be acutely dependent on LH stimulation. Progesterone production by both cell types is dependent on lipoproteins delivered by the abundant luteal blood supply. Thus, distinct cellular features of the mid-cycle corpus luteum produce considerable steroidogenic capacity.
本文综述了关于反刍动物发情周期中期黄体细胞类型的高度分化特性及其调节的文献。黄体的血管主要由内皮细胞组成，黄体内部的小动脉或动脉较少。流向黄体的血流量似乎不受促性腺激素、代谢活动或自主神经的调节，而是依赖于高血压的维持。黄体毛细血管的密度以及黄体小动脉的缺乏使得黄体血流量升高且相对不受调节。反刍动物黄体中的类固醇生成既表现出对促黄体生成素（LH）作用的依赖性，也表现出独立性。黄体的初始黄体化、生长和发育依赖于LH的作用，但反刍动物发情周期中期黄体产生孕酮相对独立于急性LH刺激。这种明显的谜团可能是由于黄体中类固醇生成细胞类型具有不同的功能特性。大黄体细胞产生孕酮相对独立于LH的作用，但小黄体细胞对LH刺激有反应。发情周期中期黄体产生的大部分孕酮是由大黄体细胞产生的，可能并不急性依赖于LH刺激。两种细胞类型产生孕酮均依赖于丰富的黄体血液供应所输送的脂蛋白。因此，发情周期中期黄体独特的细胞特征产生了相当大的类固醇生成能力。
