Campbell B K, Gordon B M, Tsonis C G, Scaramuzzi R J
CSIRO Division of Animal Production, Blacktown, NSW, Australia.
J Endocrinol. 1995 Jun;145(3):479-90. doi: 10.1677/joe.0.1450479.
Ewes with ovarian autotransplants received either inhibin antiserum (10 ml i.v. raised in sheep against recombinant 32 kDa human inhibin; n = 6) or sheep serum (10 ml i.v.; n = 5) on day 3 of the luteal phase with additional daily injections (1 ml i.v.) from 48 h after the initial bolus until day 13. Jugular and ovarian venous blood samples were taken 4-hourly over days 2-13 of the luteal phase. Blood samples were also taken at more frequent intervals (every 10-15 min for 2-3 h) to examine pulsatile secretory responses from the ovary to endogenous and gonadotrophin-releasing hormone-induced (150 ng i.m.) LH pulses on days 4, 6, 8, 10 and 12 of the luteal phase. Plasma FSH levels, ovarian steroid secretion and ovarian follicular development were measured. The ovarian follicle population was estimated daily by real time ultrasound scanning. Immunisation against inhibin resulted in a 3- to 4-fold increase (P < 0.001) in plasma FSH levels within 8 h with levels remaining elevated over controls for 6-7 days. Within 24 h of immunisation there was an increase in the number of small ovarian follicles (P < 0.05) and by 3 days after treatment immunised ewes had 4-6 large ovarian follicles/ewe with this increase in the total number of large follicles being maintained for the rest of the experimental period (P < 0.05). Mean ovarian oestradiol secretion during intensive bleeds was not different from controls 24 h after immunisation, but by 3 days after immunisation it was elevated 4- to 5-fold (P < 0.001) over controls with this increase being maintained throughout the experiment. Similar responses to immunisation against inhibin in androstenedione secretion were observed although mean androstenedione secretion was not elevated until 7 days after treatment. In vitro antibody titres in immunised ewes remained elevated but declined steadily (P < 0.001) over the experimental period. We conclude that the initial stimulation of follicle development and ovarian steroid secretion following passive immunisation against inhibin can be attributed to increased blood FSH. However, the fact that with time FSH declined but increased follicle development was sustained, despite maintenance of high circulating antibody titres, suggests that on a longer term basis inhibin immunisation may stimulate ovarian function by interfering with the modulation of follicle development by inhibin at an ovarian level.
对进行了卵巢自体移植的母羊，在黄体期第3天静脉注射抑制素抗血清（10毫升，由羊抗重组32 kDa人抑制素产生；n = 6）或羊血清（10毫升，静脉注射；n = 5），并从初始大剂量注射后48小时开始至第13天每天额外进行静脉注射（1毫升）。在黄体期的第2 - 13天，每4小时采集一次颈静脉和卵巢静脉血样。还更频繁地采集血样（每10 - 15分钟采集2 - 3小时），以检测在黄体期第4、6、8、10和12天卵巢对内源性和促性腺激素释放激素诱导（150纳克，肌肉注射）的促黄体生成素脉冲的脉冲式分泌反应。测量血浆促卵泡素水平、卵巢类固醇分泌和卵巢卵泡发育情况。每天通过实时超声扫描估计卵巢卵泡数量。用抑制素免疫后，8小时内血浆促卵泡素水平增加3至4倍（P < 0.001），且在6 - 7天内一直高于对照组。免疫后24小时内，小卵泡数量增加（P < 0.05），治疗后3天，免疫母羊每只出现4 - 6个大卵泡，大卵泡总数的增加在实验期剩余时间内持续存在（P < 0.05）。免疫后24小时，强化采血期间的平均卵巢雌二醇分泌与对照组无差异，但免疫后3天，其比对照组升高4至5倍（P < 0.001），且在整个实验过程中持续升高。在雄烯二酮分泌方面也观察到了对抑制素免疫的类似反应，尽管平均雄烯二酮分泌直到治疗后7天才升高。免疫母羊的体外抗体效价在实验期内一直升高，但呈稳定下降趋势（P < 0.001）。我们得出结论，被动免疫抑制素后对卵泡发育和卵巢类固醇分泌的初始刺激可归因于血液中促卵泡素的增加。然而，随着时间推移促卵泡素下降，但卵泡发育仍持续增加，尽管循环抗体效价维持在高水平，这一事实表明，从长期来看，抑制素免疫可能通过在卵巢水平干扰抑制素对卵泡发育的调节来刺激卵巢功能。
