Campbell B K, Baird D T, McNeilly A S, Scaramuzzi R J
Department of Obstetrics and Gynecology, University of Edinburgh.
J Endocrinol. 1990 Nov;127(2):285-96. doi: 10.1677/joe.0.1270285.
Active immunization of sheep against androstenedione results in an increase in ovulation rate that is associated with increased plasma levels of LH and progesterone, but not FSH. Although immunized ewes have more activated follicles the secretion rate of oestradiol is not increased. An experiment was conducted to examine the effect of androstenedione immunity on the ovarian secretion and peripheral plasma concentrations of inhibin. Merino ewes in which the left ovary had been autotransplanted to a site in the neck were divided into control (n = 5) and androstenedione-immune (n = 6) groups. Ovarian and jugular venous blood was collected every 10 min at two stages of the follicular phase, 21-27 h and 38-42 h after a luteolytic dose of an analogue of prostaglandin F2 alpha (PG), and every 15 min for 6 h on day 10 of the subsequent luteal phase. The ewes were monitored regularly for luteal function by measurement of the concentration of progesterone and preovulatory LH surges. The concentration of inhibin in jugular and ovarian venous plasma was determined by radioimmunoassay and ovarian secretion rates and peripheral concentrations are expressed as pg of 1-26 peptide fragment of the alpha chain. The ovarian secretion rate of inhibin tended to be greater in androstenedione-immune ewes at all stages of the oestrous cycle measured, with this difference being statistically significant (P less than 0.05) during the luteal phase (100 +/- 40 and 260 +/- 80 (S.E.M.) pg/min for control and immune groups respectively). The pattern of ovarian inhibin secretion exhibited pulsatile-like fluctuations which were not associated with LH pulses. Peripheral concentrations of inhibin were generally higher in immunized than in control ewes with this difference being significant (P less than 0.01) from day 4 to 14 of the luteal phase (59 +/- 5 and 110 +/- 7 ng/l for control and immune respectively). The ovarian secretion rate of immunoactive inhibin was greater (P less than 0.01) during the follicular phase than during the luteal phase in both groups of ewes, and peripheral concentrations of inhibin increased (P less than 0.001) following injection of PG in ewes from both treatment groups. We concluded that androstenedione immunity results in an increase in ovarian inhibin secretion, an effect that can probably be attributed to the greater number of large oestrogenic follicles present in the ovaries of these ewes.(ABSTRACT TRUNCATED AT 400 WORDS)
用雄烯二酮对绵羊进行主动免疫会导致排卵率增加，这与血浆中促黄体生成素（LH）和孕酮水平升高有关，但与促卵泡生成素（FSH）无关。尽管免疫后的母羊有更多活化的卵泡，但雌二醇的分泌率并未增加。进行了一项实验以研究雄烯二酮免疫对卵巢抑制素分泌及外周血浆浓度的影响。将左卵巢自体移植到颈部某部位的美利奴母羊分为对照组（n = 5）和雄烯二酮免疫组（n = 6）。在卵泡期的两个阶段，即注射溶黄体剂量的前列腺素F2α（PG）类似物后21 - 27小时和38 - 42小时，每隔10分钟采集一次卵巢和颈静脉血，并在随后黄体期的第10天每隔15分钟采集6小时。通过测量孕酮浓度和排卵前促黄体生成素高峰定期监测母羊的黄体功能。通过放射免疫测定法测定颈静脉和卵巢静脉血浆中抑制素的浓度，卵巢分泌率和外周浓度以α链1 - 26肽片段的皮克数表示。在所测量的发情周期的所有阶段，雄烯二酮免疫的母羊卵巢抑制素分泌率往往更高，在黄体期这种差异具有统计学意义（P < 0.05）（对照组和免疫组分别为100 ± 40和260 ± 80（标准误）皮克/分钟）。卵巢抑制素分泌模式呈现出类似脉冲的波动，与促黄体生成素脉冲无关。免疫母羊外周抑制素浓度通常高于对照母羊，在黄体期第4天至14天这种差异显著（P < 0.01）（对照组和免疫组分别为59 ± 5和110 ± 7纳克/升）。两组母羊中，卵泡期免疫活性抑制素的卵巢分泌率均高于黄体期，且两组母羊注射PG后外周抑制素浓度均升高（P < 0.001）。我们得出结论，雄烯二酮免疫导致卵巢抑制素分泌增加，这种效应可能归因于这些母羊卵巢中存在更多大的雌激素生成卵泡。（摘要截选至400字）
