Rao C V, Ireland J J, Roche J F
Mol Cell Endocrinol. 1984 Feb;34(2):99-105. doi: 10.1016/0303-7207(84)90060-1.
Luteal gonadotropin receptors decrease in cows, sheep and rats within 24 h following an injection of a luteolytic dose of prostaglandin (PG) F2 alpha. But it is not known whether this decrease is the specific event, or a reflection of general decline in luteal cell structure, function and metabolism. In order to investigate this possibility, 15 of 21 heifers were given on day 9 of the estrous cycle, a single 500 micrograms injection of Cloprostenol (CO), a synthetic PGF2 alpha analog. These heifers were ovariectomized in groups of 5 at 12, 24 and 36 h after CO. For controls, a group of 6 heifers were ovariectomized just prior to injection of the others. Serum progesterone levels decreased whereas LH levels increased (P less than 0.05) by 12 h with no additional changes observed at 24 or 36 h. The luteal plasma membranes [125I]hCG specific binding, as well as 5'-nucleotidase (5'-NE) activity, decreased by 12 h and continued to decline (P less than 0.05) until 24 h (binding) or 36 h (5'-NE). Scatchard analysis showed that the decrease in [125I]hCG binding was due to a decrease in receptor number rather than a decrease in receptor affinity. The activities of cytochrome c oxidase in mitochondria, NADH cytochrome c reductase in rough endoplasmic reticulum and galactosyl transferase in Golgi decreased while NAD pyrophosphorylase in nuclei virtually disappeared following the injection of CO. The beta-N-acetyl-D-glucosaminidase (a lysosomal hydrolase) activity in the homogenate increased by 12 h and continued to increase up to 36 h.(ABSTRACT TRUNCATED AT 250 WORDS)
在注射溶黄体剂量的前列腺素（PG）F2α后的24小时内，奶牛、绵羊和大鼠的黄体促性腺激素受体减少。但尚不清楚这种减少是特定事件，还是黄体细胞结构、功能和代谢普遍下降的反映。为了研究这种可能性，在发情周期的第9天，给21头小母牛中的15头单次注射500微克氯前列醇（CO），一种合成的PGF2α类似物。这些小母牛在注射CO后的12、24和36小时，按每组5头进行卵巢切除。作为对照，一组6头小母牛在其他小母牛注射前即刻进行卵巢切除。血清孕酮水平下降，而促黄体生成素（LH）水平在12小时时升高（P<0.05），在24或36小时未观察到进一步变化。黄体细胞膜[125I]人绒毛膜促性腺激素（hCG）特异性结合以及5'-核苷酸酶（5'-NE）活性在12小时时下降，并持续下降（P<0.05），直到24小时（结合）或36小时（5'-NE）。Scatchard分析表明，[125I]hCG结合的减少是由于受体数量减少而非受体亲和力降低。注射CO后，线粒体中的细胞色素c氧化酶、粗面内质网中的NADH细胞色素c还原酶和高尔基体中的半乳糖基转移酶活性下降，而细胞核中的NAD焦磷酸化酶几乎消失。匀浆中的β-N-乙酰-D-氨基葡萄糖苷酶（一种溶酶体水解酶）活性在12小时时增加，并持续增加至36小时。（摘要截断于250字）
