Baird D T, Campbell B K, McNeilly A S
Department of Obstetrics and Gynaecology, University of Edinburgh.
J Endocrinol. 1990 Oct;127(1):23-32. doi: 10.1677/joe.0.1270023.
An experiment was conducted to examine the effect of steroid-free ovine follicular fluid (oFF) on ovarian hormone secretion. Eight Merino x Finnish Landrace ewes in which the left ovary and vascular pedicle had been autotransplanted to a site in the neck were studied during the breeding season. Luteal regression was induced in all animals by injection of cloprostenol (100 micrograms, i.m.) on day 10 of the luteal phase. Four of the eight animals were treated with steroid-free oFF (3 ml, s.c.) in the early follicular phase, 24 and 36 h after injection of cloprostenol. Samples of both ovarian and jugular venous blood were collected at 4-h intervals from 20 h before until 96 h after injection of cloprostenol. Ovarian and jugular venous blood samples were also collected at 10-min intervals from 48 to 52 h after injection of cloprostenol to investigate the pattern of pulsatile secretion of ovarian hormones. Samples were assayed for oestradiol, androstenedione, testosterone and inhibin and the ovarian secretion rates calculated. Both injections of oFF resulted in a fourfold increase in the concentration of inhibin in jugular venous plasma within 4-8 h of administration (P less than 0.01) with concentrations remaining increased (P less than 0.05) until 56 h after cloprostenol (32 h after the first oFF injection). Following oFF injection there was a profound (100%; P less than 0.001) and prolonged decrease in the peripheral concentration of FSH until 60 h after cloprostenol at which time the concentration of FSH increased five- to sixfold (P less than 0.001) to a peak lasting 24 h. In contrast to FSH, the concentration of LH in jugular venous plasma rose immediately following oFF treatment and continued to increase, exhibiting a profile similar to that described for FSH. No preovulatory LH surge was detected in any of the oFF-treated ewes while untreated ewes had an LH surge within 58.0 +/- 1.2 (S.E.M.) h. Within 8 h of the first injection of oFF the ovarian secretion rate of oestradiol, androstenedione and inhibin began to decline to reach a nadir of less than 1 ng/min within 32-36 h (56-60 h after cloprostenol; P less than 0.01). Testosterone secretion, already barely detectable, did not change significantly following injection of oFF but remained low for 36 h following oFF and did not exhibit the increase observed over this period in controls. After injection of oFF the episodic secretion of oestradiol, androstenedione, testosterone and inhibin was markedly suppressed in spite of numerous pulses of LH.(ABSTRACT TRUNCATED AT 400 WORDS)
进行了一项实验，以研究无类固醇的绵羊卵泡液（oFF）对卵巢激素分泌的影响。在繁殖季节，对8只美利奴羊×芬兰长白母羊进行了研究，这些羊的左卵巢和血管蒂已自体移植到颈部的一个部位。在黄体期第10天，通过肌肉注射氯前列醇（100微克）诱导所有动物黄体退化。8只动物中的4只在卵泡早期、注射氯前列醇后24和36小时接受无类固醇oFF（3毫升，皮下注射）治疗。从注射氯前列醇前20小时到注射后96小时，每隔4小时采集卵巢和颈静脉血样本。在注射氯前列醇后48至52小时，每隔10分钟采集卵巢和颈静脉血样本，以研究卵巢激素的脉冲分泌模式。对样本进行雌二醇、雄烯二酮、睾酮和抑制素检测，并计算卵巢分泌率。两次注射oFF均导致给药后4至8小时内颈静脉血浆中抑制素浓度增加四倍（P<0.01），浓度持续升高（P<0.05），直至氯前列醇注射后56小时（首次注射oFF后32小时）。注射oFF后，FSH外周浓度显著（100%；P<0.001）且持续降低，直至氯前列醇注射后60小时，此时FSH浓度增加五至六倍（P<0.001），达到峰值并持续24小时。与FSH相反，颈静脉血浆中LH浓度在oFF治疗后立即升高，并持续增加，其变化趋势与FSH相似。在接受oFF治疗的任何母羊中均未检测到排卵前LH峰，而未治疗的母羊在58.0±1.2（标准误）小时内出现LH峰。在首次注射oFF后8小时内，雌二醇、雄烯二酮和抑制素的卵巢分泌率开始下降，在32至36小时内（氯前列醇注射后56至60小时）降至最低点，低于1纳克/分钟（P<0.01）。睾酮分泌本来就几乎检测不到，注射oFF后没有明显变化，但在注射oFF后36小时内一直很低，且未表现出在此期间对照组中观察到的增加。注射oFF后，尽管有多次LH脉冲，雌二醇、雄烯二酮、睾酮和抑制素的脉冲分泌仍受到明显抑制。（摘要截短至400字）
