Lewis C E, Megson A, Morris J F, Charlton H M
J Endocrinol. 1986 Dec;111(3):483-93. doi: 10.1677/joe.0.1110483.
We have investigated the effects of multiple 2-hourly injections of LH-releasing hormone (LHRH) on the number and size of the gonadotrophs and gonadotroph secretory granules, and the lipid content of gonadotrophs in the pituitary glands of intact and gonadectomized male and female hypogonadal (hpg) mice. Gonadotrophs were identified by immunocytochemistry for LH beta, and the size and secretory status of the gonadotrophs were assessed by quantitative ultrastructural analysis of immunoidentified gonadotrophs. The administration of 60 ng LHRH by subcutaneous injection every 2 h for 15 days resulted in an increase in the number, size and granule content of LH beta-immunoidentified gonadotrophs of hpg mice to values found in normal adult mice. Large lipid droplets accumulated in 30-40% of the gonadotrophs in both male and female LHRH-treated hpg mice. Although lipid-containing gonadotrophs were larger than lipid-free cells in all LHRH-treated groups irrespective of the presence or absence of gonads, a marked difference in the number, position within the cell, and size of the secretory granules between the lipid-containing and lipid-free cells was found only in the pituitary glands of intact LHRH-treated hpg females. These results demonstrate: (a) that the effects of multiple injections of LHRH on the morphology of the gonadotrophs of hpg mice is not dependent on the presence of functioning gonads, although ovarian factors are required for the full development of morphological, and hence possibly functional, heterogeneity in the gonadotroph population in female animals, and (b) that, although multiple injections of LHRH in hpg mice are more effective than single daily injections of LHRH in stimulating pituitary-gonadal function, there is no obvious difference in the morphologically recognizable effects that these two modes of administration have on the pituitary gonadotrophs.
我们研究了每2小时多次注射促黄体生成素释放激素（LHRH）对性腺功能减退（hpg）的完整和性腺切除的雄性及雌性小鼠垂体中促性腺激素细胞的数量和大小、促性腺激素分泌颗粒以及促性腺激素细胞脂质含量的影响。通过对促黄体生成素β亚基进行免疫细胞化学鉴定促性腺激素细胞，并通过对免疫鉴定的促性腺激素细胞进行定量超微结构分析来评估促性腺激素细胞的大小和分泌状态。每2小时皮下注射60 ng LHRH，持续15天，导致hpg小鼠中促黄体生成素β免疫鉴定的促性腺激素细胞的数量、大小和颗粒含量增加至正常成年小鼠的水平。在接受LHRH治疗的雄性和雌性hpg小鼠中，30 - 40%的促性腺激素细胞中积累了大的脂滴。尽管在所有接受LHRH治疗的组中，无论有无性腺，含脂促性腺激素细胞都比无脂细胞大，但仅在接受LHRH治疗的完整hpg雌性小鼠的垂体中，发现含脂和无脂细胞之间在分泌颗粒的数量、细胞内位置和大小上存在显著差异。这些结果表明：（a）多次注射LHRH对hpg小鼠促性腺激素细胞形态的影响不依赖于功能性性腺的存在，尽管卵巢因素是雌性动物促性腺激素细胞群体中形态学以及可能功能异质性充分发展所必需的；（b）虽然在hpg小鼠中多次注射LHRH比每日单次注射LHRH在刺激垂体 - 性腺功能方面更有效，但这两种给药方式对垂体促性腺激素细胞在形态上可识别的影响没有明显差异。
