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1.
精浆中催乳素浓度与精子活动力的关系及临床意义   总被引:1,自引:0,他引:1  
目的 :探讨精浆中催乳素 (PRL)浓度与精子活动力和活动率的关系。方法 :选择不育症门诊中 6 0例男子进行精液分析 ,按精子活动力和活动率分成 A组 (活动力 ~ 级 ,活动率 >5 0 % )和 B组 (活动力 ~ 级、活动率≤5 0 % )。应用磁分离酶联方法测定其精浆中 PRL 浓度。结果 :A组精浆中 PRL 浓度为 (14.85± 4.0 5 ) μg/ L,B组为 (19.5 5± 4.85 ) μg/ L,A组与 B组之间 PRL 浓度差异有显著性 (P<0 .0 0 1)。精子活动力和活动率与精浆中 PRL 浓度呈负相关。结论 :血清和精浆中 PRL以不同方式进行调节 ,精浆中 PRL 来源于精囊 ,其浓度的高低影响着精子活动力和活动率。临床上不育症患者 ,采用分步射精法 ,摒弃后半部分精液 ,可能提高精子功能状态和受孕率  相似文献   
2.
[目的]探索催乳素释放肽(PrRP)在青年摩杂一代水牛生殖调控和泌乳中的作用。[方法]应用石蜡切片、HE染色、Nissl染色、免疫组化染色,对5头雌性的青年摩杂一代水牛下丘脑一垂体一卵巢轴上PrRP的分布进行定位,并与LEICA图像分析系统和sPSSl3.0统计分析软件相结合进行统计。[结果]在下丘脑内,PrRP免疫反应阳性神经元主要分布在视上核,在后核分布最少;PrRP免疫反应阳性纤维在室旁核高度密集,在弓状核、乳头体核密集,在视前核、前核、视交叉上核、腹内侧核、腹外侧核、背内侧核、背外侧核只有少量分布.在视上核无免疫反应阳性纤维。在垂体,在腺垂体部只观察到PrRP免疫反应阳性细胞,无免疫反应阳性纤维;在神经垂体部,有大量的免疫反应阳性纤维,无免疫反应阳性细胞。在卵巢的卵泡和间质中未见PrRP免疫反应阳性产物,仅在黄体的粒性细胞中发PrRP.癌反应阳性产物.[结论]PrRP广泛分布在青年靡杂一代水牛下丘脑一垂体一卵巢轴上的各个环节。  相似文献   
3.
催乳素及其受体对乳腺发育研究进展   总被引:4,自引:0,他引:4  
本文主要对催乳素受体的结构、作用机理、功能及其在不同时期的乳腺发育的不同作用进行的论述。总结了近几年来的有关研究进展,为进一步的研究工作提供参考资料。  相似文献   
4.
The purpose of this study was to investigate the changes in serum concentrations of prolactin (PRL), progestagens, and estradiol-17β and biochemical parameters during peripartum in an agalactic mare, as well as to study the periparturient indices of the foal. A 4-year-old Thoroughbred, primiparous, pregnant mare was diagnosed as agalactic from clinical conditions such as absence of observable udder development and weight loss of her foal after parturition. Serum PRL concentrations of the agalactic mare during prepartum tended to be lower than those of the control mares (19.5 ng/mL and 67.0 ± 15.0 ng/mL on the day of parturition, respectively). The progestagens and estradiol-17β concentrations were not markedly different between the agalactic mare and the control mares. Concentrations of γ-glutamyl transferase of the agalactic mare were higher than those of the control mares (P < .05). Although the serum immunoglobulin G concentrations of the foal of the agalactic mare after 24 hours of age were lower than those of the foals of the control mares (P < .05), all periparturient indices regarding the agalactic mare were considered to be within the normal range. In contrast, insufficient udder development and milk production was observed in the agalactic mare through the pre- and postpartum periods. We have ruled out the known causes for agalactia in mares based on other parameters, clinical symptoms, and nutritional causes. Clinical symptoms and PRL parameters in this case report are consistent with the category of agalactia in mares of unexplained causes, and we have determined additional blood parameters associated with agalactia in mares that are consistent with this category.  相似文献   
5.

Optimal use of limited resources as nucleus and testing capacity is important when organizing crossbreeding schemes in pigs. This paper introduces a method of modelling pig crossbreeding schemes consisting of nucleus, multiplier and commercial tiers. As an efficient alternative to the gene flow method (Hill, W.G. 1974. Anim. Prod. 18, 117-139), lag, original genetic level and annual genetic improvement for each line and cross are combined into one single evaluation criterion, the average discounted revenues of the breeding scheme. An optimum allocation of nucleus and testing capacity within breeding schemes, as well as an optimum solution between schemes can be found. As an example, the optimization of a four-way crossbreeding scheme is shown. the optimum allocation of nucleus capacity was 35% and 15% in each dam line and sire line, respectively. The corresponding figures for testing capacity were 23% and 27%.  相似文献   
6.

Background

Integration of behavioral observations with traditional selection schemes may lead to enhanced animal well-being and more profitable forage-based cattle production systems. Brahman-influenced (BR; n = 64) and Gelbvieh × Angus (GA; n = 64) heifers consumed either toxic endophyte-infected tall fescue (E+) or one of two nontoxic endophyte-infected tall fescue (NT) cultivars during two yr. Heifers were weighed at midpoint and termination of grazing. Grazing behavior (grazing, resting in the shade, lying, or standing without grazing) was recorded (n = 13 visual observations per yr in June and July) for each pasture. During yr 2, exit velocity (EV) and serum prolactin (PRL) were determined.

Results

Grazing behavior was influenced (P < 0.05) by an interaction between fescue cultivar and breed type. Gelbvieh × Angus heifers assigned to E+ pastures had the lowest percentage of animals grazing and the largest percentage of animals resting in the shade. Brahman-influenced heifers had faster EV (P < 0.001) than GA heifers (0.52 vs. 0.74 ± 0.04 s/m, respectively). Body weight (BW) was affected (P < 0.01) by an interaction of tall fescue cultivar and d, and an interaction of tall fescue cultivar and breed type. Heifers grazing NT pastures were heavier (P < 0.01) than heifers grazing E+ pastures at midpoint and termination. Gelbvieh × Angus heifers grazing NT pastures were heavier (P < 0.01) than GA and BR heifers grazing E+ and BR heifers grazing NT pastures. An interaction of forage cultivar and breed type occurred on serum PRL (P < 0.01).

Conclusion

Collectively fescue cultivar, EV, and concentrations of serum PRL were associated with grazing behavior. Heifers grazing NT pastures were observed to be grazing more than heifers assigned to E+ pastures, regardless of breed type, which may have contributed to changes in BW and average daily gain (ADG) in heifers. Integration of behavioral observations along with traditional selection schemes may lead to enhanced animal well-being and more profitable forage-based cattle production systems.  相似文献   
7.
The aims of the present study were to determine whether salsolinol (SAL), a dopamine-related compound, is present in the bovine posterior pituitary (PP) gland, and to clarify the effect of SAL on the secretion of prolactin (PRL) in ruminants. SAL was detected in extract of bovine PP gland using high-pressure liquid chromatography with electrochemical detection (HPLC-EC). A single intravenous (i.v.) injection of SAL (5 and 10mg/kg body weight) significantly and dose-dependently stimulated the release of PRL in goats (P<0.05). Plasma PRL levels reached a peak 10min after the injection, then gradually returned to basal values in 60-80min. The PRL-releasing pattern was similar to that in response to sulpiride (a dopamine receptor antagonist). The intracerebroventricular (i.c.v.) injection of 1mg of SAL had no significant effect on the release of PRL in calves, however, 5mg significantly stimulated the release (P<0.05) with peak values reached 30-40min after the injection. Moreover, SAL significantly stimulated the release of PRL from cultured bovine anterior pituitary cells at doses of 10(-6) and 10(-5)M, compared to control cells (P<0.05). Taken together, our data clearly show that SAL is present in extract of the PP gland of ruminants, and has PRL-releasing activity both in vivo and in vitro. Therefore, this endogenous compound is a strong candidate for the factor having PRL-releasing activity that has been previously detected in extract of the bovine PP gland.  相似文献   
8.
The autumn transition is characterized by a number of anomalies affecting the luteal phase of the estrous cycle, such as declining progesterone secretion from the corpus luteum and increased rate of failure of luteolysis. Prolactin also decreases. We theorized that these events may be linked, possibly through dopamine. We administered domperidone, a specific dopamine D2 receptor antagonist from September 12 to anestrus or January 15, either daily (n = 8), or once per day for the first 7 days of each month (n = 7). Controls (n = 7) received no treatment. Mean progesterone and prolactin concentrations were compared with summer cycles. Time to entry into anestrus and incidence of spontaneously prolonged luteal activity was compared between groups during the autumn transition. Prolactin declined from June through October equally in all groups. There was no difference between groups in time to anestrus. Progesterone decline was prevented (daily treatment) or delayed for a prolonged period (weekly group) in autumn. The incidence of spontaneously prolonged corpus luteum activity was reduced to summer levels in both domperidone groups compared with the control. We concluded that autumn prolactin decline was not driven through dopaminergic D2 receptor inhibition of pituitary lactotrophs. Sustained progesterone synthesis through the autumn may be the result of action of the D2 receptor antagonist with dopamine receptors on the corpus luteum. Autumnal luteolytic function appears to have a dopamine-influenced component. There does not appear to be a causative relationship between autumnal progesterone and prolactin secretion.  相似文献   
9.
具有泌乳功能的乳腺上皮细胞系可作为乳腺发育学、乳腺病理学、泌乳生物工程学研究的细胞模型,本研究测定了激素对奶牛乳腺上皮细胞系泌乳功能的影响,为阐述泌乳机制提供工作基础。应用HPLC方法对体外培养奶牛乳腺上皮细胞的酪蛋白和乳糖的分泌情况和细胞培养液中的酪蛋白、乳糖含量进行测定,以确定胰岛素、催乳素和孕酮处理后的奶牛乳腺上皮细胞的泌乳功能。试验结果表明:奶牛乳腺上皮细胞具有酪蛋白和乳糖的分泌能力,在72h内,随着细胞培养时间延长,胰岛素处理组细胞中的酪蛋白和乳糖的升高趋势不明显,孕酮处理组升高趋势较明显,催乳素处理组升高趋势很明显;胰岛素处理组、催乳素处理组和孕酮处理组细胞培养液中酪蛋白升高趋势均很明显,乳糖含量均很高,三组激素比较而言,胰岛素处理组乳糖含量最高。此外,三组激素对乳腺上皮细胞活力影响均很大,在72h之内,总体变化为:催乳素处理组和孕酮处理组细胞活力均升高,胰岛素处理组细胞活力下降。  相似文献   
10.
The aim of the present study was to investigate possible relationships between plasma concentrations of prolactin and the following factors throughout gestation in lactating dairy cows: photoperiod, season, milk production, Neospora caninum-seropositivity, twin pregnancy, and plasma concentrations of pregnancy associated glycoproteins-1 (PAG-1), progesterone and cortisol. Pregnancy was diagnosed by trans-rectal ultrasonography on Day 40 post-insemination and by palpation per rectum on Days 90, 120, 150, 180 and 210 or until abortion in aborting cows. Blood samples were collected from each animal immediately before each pregnancy diagnosis. The study population was comprised of 73 non-aborting (54 Neospora-seropositive cows) and 20 aborting cows (all Neospora-seropositive) cows. In non-aborting cows, GLM repeated measures of analysis of variance revealed that lactation number and days in milk had no effect on plasma prolactin concentrations throughout gestation, whereas high plasma prolactin concentrations were significantly associated with high plasma levels of cortisol and PAG-1, with Neospora-seropositivity, positive photoperiod (increasing day length), twin pregnancy, and with low plasma progesterone concentrations. An interaction among plasma prolactin, plasma cortisol and milk production was observed in that plasma prolactin concentrations differed significantly throughout gestation and were highest in high-producing cows with high cortisol levels. In Neospora-seropositive non-aborting versus aborting cows, mean prolactin concentrations failed to differ on Days 40, 90, 120, 150 and 180 of pregnancy, whereas prolactin values were significantly lower (P = 0.03) in aborting animals on Day 210 of pregnancy. Our results indicate that a positive photoperiod and Neospora-infection lead to increased plasma prolactin concentrations throughout gestation. Reduced prolactin concentrations detected in Neospora-seropositive aborting cows compared to non-aborting animals suggests a protective effect of prolactin in N. caninum infection.  相似文献   
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