内源性和外源性雌二醇对绵羊黄体溶解的作用

20只绵羊随机按双因子试验设计分为4个处理组,双因子为X-射线照射卵巢选择性破坏卵泡和埋植雌二醇。X-射线照射使发情周期黄体期延长,雌二醇使这种作用逆转。子宫内膜催产素受体浓度决定于黄体溶解发生的时间,即黄体溶解较早发生羊只子宫内膜催产素受体浓度低于黄体溶解发生较晚或尚未发生的羊只。催产素和PGFM均呈现明显的分泌波。雌二醇处理缩短PGFM峰值间隔时间、延长催产素峰值间隔时间,可能存在一种不依赖于催产素的PGF_(2α)释放;雌二醇对这种不依赖于催产素的PGF_(2α)释放有着重要作用。     

Effect of Administration of Oxytocin During Diestrus on Corpus Luteum Function and Endometrial Oxytocin Receptor Concentration in Cycling Mares

The objectives of this study were to (1) compare the effect of twice versus once daily administration of oxytocin on days 7-14 after ovulation on the duration of corpus luteum (CL) function and (2) determine the effect of oxytocin treatment on endometrial oxytocin receptor concentration in mares. In experiment 1, mares were randomly assigned to three groups on day 7: (1) untreated control group (n = 7), (2) twice daily oxytocin treatment group (n = 7), and (3) once daily oxytocin treatment group (n = 8). Oxytocin-treated mares received 60 U of oxytocin intramuscularly (IM) the respective number of times each day on days 7 through 14. One of seven control mares (14%), five of seven (71%) twice daily oxytocin-treated mares, and five of eight (63%) once daily oxytocin-treated mares had prolonged CL function. There was no significant difference in the proportion of mares with prolonged CL function between the two oxytocin-treated groups, and collectively, oxytocin treatment increased (P < .05) the proportion of mares with prolonged CL function compared with no treatment. In experiment 2, mares were randomly assigned to two groups (n = 5/group): (1) saline-treated control mares, and (2) oxytocin-treated mares. Beginning on day 7, control mares received 3 mL of sterile saline IM twice daily, and oxytocin-treated mares received 60 U of oxytocin IM twice daily through day 14. On day 15, endometrial oxytocin-binding capacity was determined (as a measure of oxytocin receptor concentration), and there was no difference (P > .1) between control and oxytocin-treated mares (1,465.7 ± 108 and 1,382.8 ± 108 fmol/mg protein [mean ± standard error of mean], respectively).     

Hormone manipulation to overcome a major barrier in male catfish spawning: The role of oxytocin augmentation in inducing voluntary captive spawning

A major challenge in Clariid catfish seed production is our inability to induce voluntary captive spawning of the brooders. Since voluntary captive spawning had been previously elicited in a Clarias species by simulating natural breeding environment, we speculated that the major obstacle in voluntary spawning might be the absence of an inducing agent that triggers mating response in the brooders. To address the issue, oxytocin was injected to the brooders along with Ovatide (a commercial inducing agent comprising salmon gonadotropin‐releasing hormone analogue and domperidone). Administration of 40 mIU/kg body weight of oxytocin after 12 hr of Ovatide injection resulted in voluntary spawning of the fish (81.5%, i.e. 31 out of 38 trials), with more than 70% hatching rate in simple and low‐cost spawning facilities. Histology of male gonads indicated sustained gamete maturation and the gonads were observed to be visibly turgid in the fish that received both the hormones. In contrast, gamete maturation slackened after 10 hr in the control fish, injected with Ovatide only. Administration of oxytocin along with Ovatide was also observed to induce aggressive sexual behaviour among the males. Neither of the hormones, acting alone, could induce voluntary spawning in the fish or influence sexual behaviour. Our results clearly show that oxytocin plays a significant role in sustaining the male gamete maturation induced by Ovatide and trigger the behavioural mating response, leading to voluntary spawning in C. magur. The results hold potential to make a paradigm shift in the commercial catfish seed production technology.     

外周器官催产素细胞定位研究进展

催产素是一种经典内分泌激素，放射免疫测定法（RIA）等的研究结果已表明OT不仅产生于神经系统，而且在几个外周器官也有存在。本文从OT细胞定位研究的角度出发，对近年来在卵巢、子宫、胎盘、睾丸及肾上腺、胸腺、胰腺等外周器官中催产素的分布情况及其作用方面的研究进展进行综述。     

妊娠期奶山羊下丘脑GnRH和OT免疫反应双标记细胞的分布

为了探讨促性腺激素释放激素（GnRH）和催产素（OT）是否在下丘脑细胞中共存,采用免疫组织化学双标记法对妊娠期奶山羊下丘脑中GnRH与OT的分布进行了检测。结果显示：室旁核、视上核、视前交叉上核、弓状核、下丘脑外侧区、乳头体内侧核、乳头体后核等核团（区）有GnRH和OT免疫反应双标记细胞,在妊娠的不同时期,GnRH和OT免疫反应双标记细胞数量有显著差异。这些结果为GnRH与OT相互调节提供了形态学证据。     

花的一年两次人工繁殖技术研究

北盘江光照库区增殖放流站通过调节水温水质、增加冲水次数,强化营养等措施,可使花亲鱼一年两次性成熟,并且使花的两次产卵受精率达80%以上,实现一年两次催产。研究结果表明,该技术可以大大提高亲鱼产卵量,提高了亲鱼利用率,极大地满足了实际需求,可为鱼类繁殖提供参考。     

摘除卵巢绵羊经雌激素处理后子宫催产素受体的测定

给摘除卵巢绵羊埋植雌激素后，采取其子宫肉阜、肉阜间子宫内膜、肌层和其他器官组织样品用于催产素受体（ｒＯＴ）测定。３种子宫组织和输卵管含有ｒＯＴ；阴道、肌肉、小肠、肝组织中ｒＯＴ浓度不可测。子宫组织中ｒＯＴ仅具有单一类型的结合点，Ｋｄ值为１．３５ｎｍｏｌ／Ｌ，最大结合容量为３０２．８ｆｍｏｌ／ｍｇ蛋白。     

催产素免疫反应神经元在鸡下丘脑的定位——PAP法研究

应用免疫组化PAP法(非标记抗体过氧化物酶-抗过氧化物酶法)研究了鸡下丘脑催产素(Oxytocin,OT)免疫反应阳性神经元的分布.结果,OT阳性神经元存在于下丘脑室旁核各亚核、视前室旁核、视上核、视前大细胞核、下丘脑外侧核、室周核、室周弓状核,在下丘脑背侧区、视前外侧区和丘脑背外侧核也有零星的OT阳性神经元,视上背侧交叉和正中隆起存在大量的OT阳性纤维和纤维末梢.此外,还观察到视前区和下丘脑前部脑基底表面以及视上核的外缘有OT阳性神经元和纤维(?)达脑的外表,在第三脑室室管膜上存在OT阳性神经元,室旁核的OT阳性细胞突起伸入到室管膜上或突出于第三脑室室腔。结果表明,OT阳性神经元在下丘脑的分布较广泛,OT向脑脊液的释放可能是多途径的.     

奶山羊下丘脑中催产素神经元的分布——ABC法研究

分泌催产素的神经元主要分布在室旁核(59.1％)和视上核(17.9％),此外在穹窿周核、腹内侧核、腹外侧核、交叉上核和乳头体外侧核较多(各约占2％～4％),有少量分布在弓状核、室周核、背内侧核、环核、前连合核、下丘脑前核、下丘脑外侧区,乳头体上核、乳头体内侧核(各1％左右)。阳性神经纤维仅见于室旁核、下丘脑前核、视上核、交叉上核等少数核团,在正中隆起和第三脑室室周可见到一定数量的阳性神经纤维。