Ganesh C B, Yajurvedi H N
Department of Zoology, Karnatak Science College, Dharwad 580 001, India.
Gen Comp Endocrinol. 2003 Oct 1;133(3):305-13. doi: 10.1016/s0016-6480(03)00186-2.
Administration (ip) of an opioid peptide, beta-endorphin (beta-EP) (0.1, 0.5, or 1 microg beta-EP/day/lizard for 30 days) during seasonal recrudescence phase of the ovarian cycle inhibited ovarian recrudescence as shown by the absence of vitellogenic follicles in the ovary in contrast to their presence in treatment controls in the lizard Mabuya carinata. In the germinal bed, treatment of 0.1 microg beta-EP did not affect primordial follicles, whereas their mean number was significantly lower in lizards treated with 0.5 or 1 microg beta-EP compared to those of treatment controls. There was also suppression of oviductal development as shown by a significantly lower relative weight of the oviduct and regressed oviductal glands in lizards treated with all the dosages of beta-EP compared to treatment controls. In another experiment, administration of FSH (10 IU FSH/alternate day/lizard for 30 days) during the regression phase of the ovarian cycle induced development of vitellogenic follicles, whereas the treatment controls showed only previtellogenic follicles. In addition, there was a significant increase in the ovarian and oviductal weights compared to initial and treatment controls. However, simultaneous administration of similar dosage of FSH and beta-EP (0.5 microg/day/lizard) did not induce ovarian recrudescence as shown by the absence of vitellogenic follicles in the ovary and significantly lower weight of the ovary and the oviduct and the mean number of oogonia, oocytes, and primordial follicles compared to those of FSH-treated lizards. The results indicate that beta-EP inhibits seasonal as well as FSH-induced ovarian recrudescence. Inhibitory effect of beta-EP on follicular development despite FSH administration implies its effect at the ovarian level in M. carinata. While adversely affecting the ovarian follicular development, beta-EP did not affect the adrenal gland as there was no significant variation in the mean nuclear diameter of the adrenocortical cells of treatment controls and beta-EP-treated lizards. Furthermore, administration of beta-EP caused a significant decrease in the mean number of islands of white pulp of the spleen indicating its adverse effect on immunity.
在卵巢周期的季节性复发阶段腹腔注射（ip）阿片肽β-内啡肽（β-EP）（0.1、0.5或1微克β-EP/天/蜥蜴，持续30天）可抑制卵巢复发，与治疗对照的变色蜥（Mabuya carinata）卵巢中存在卵黄生成卵泡相反，注射β-EP的蜥蜴卵巢中没有卵黄生成卵泡。在生发层，0.1微克β-EP的处理对原始卵泡没有影响，而与治疗对照相比，用0.5或1微克β-EP处理的蜥蜴中原始卵泡的平均数量显著更低。与治疗对照相比，所有剂量β-EP处理的蜥蜴输卵管相对重量显著更低且输卵管腺退化，这也表明输卵管发育受到抑制。在另一项实验中，在卵巢周期的消退阶段注射促卵泡激素（FSH）（10国际单位FSH/隔天/蜥蜴，持续30天）可诱导卵黄生成卵泡发育，而治疗对照仅显示前卵黄生成卵泡。此外，与初始状态和治疗对照相比，卵巢和输卵管重量显著增加。然而，同时注射相似剂量的FSH和β-EP（0.5微克/天/蜥蜴）并未诱导卵巢复发，与FSH处理的蜥蜴相比，卵巢中没有卵黄生成卵泡，卵巢和输卵管重量显著更低，卵原细胞、卵母细胞和原始卵泡的平均数量也显著更低。结果表明，β-EP抑制季节性以及FSH诱导的卵巢复发。尽管注射了FSH，但β-EP对卵泡发育的抑制作用意味着其在变色蜥的卵巢水平发挥作用。虽然β-EP对卵巢卵泡发育有不利影响，但它对肾上腺没有影响，因为治疗对照和β-EP处理的蜥蜴肾上腺皮质细胞的平均核直径没有显著差异。此外，注射β-EP导致脾脏白髓岛的平均数量显著减少，表明其对免疫有不利影响。
