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1.
用免疫组化ABC法,对发情周期中奶山羊下丘脑—全体—卵巢轴催产素(OT)分布进行了观察研究。结果表明,下丘脑中分泌OT的神经元主要分布在室旁核和视上核,在穿窿周核、腹内侧核、腹外侧核、交叉上核、背内侧核、乳头体、下丘脑外侧区、下丘脑前核等核团也有一定数量的阳性神经元;阳性神经纤维仅见于室旁核、下丘脑前核、视上核等少数核团,在正中隆起和第3脑室室周可见到一定数量的阳性神经纤维。在全体前叶未见到OT免疫反应阳性产物,自垂体柄和正中隆起的一例可见到平行排列的OT阳性神经纤维断续地延伸至神经部。卵巢的卵泡及间质未见OT免疫阳性反应,在黄体组织中存在数量较多的免疫反应阳性细胞,阳性细胞主要呈圆形、卵圆形,小梁两侧及黄体中央近腔区域的阳性细胞呈长梭形,有相当数量的阳性细胞具有突起。连续切片HE染色对照观察显示,黄体中OT主要由大黄体细胞产生,但小黄体细胞也存在OT免疫阳性反应。  相似文献   

2.
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.  相似文献   

3.
应用免疫组织化学SP法和原位杂交法研究了催产素(oxytocin,OT)及OT mRNA在成年发情期奶山羊下丘脑中的分布和表达。结果,OT免疫反应阳性细胞主要分布在视上核和室旁核,在视上弥散核、弓状核、室周核和乳头体各核团也存在免疫阳性神经元;在室旁核、视上弥散核、正中隆起和第三脑室附近有较多数量的强阳性神经纤维,在交叉上核有少量阳性神经纤维。在下丘脑23个核团(区)中均能检测出OT mRNA的阳性细胞。结果表明,OT和OT mRNA在下丘脑中分布广泛,且OT可能通过轴突传递和血液运输,将OT mRNA合成的OT运送到别的核团;OT在奶山羊发情过程中发挥了重要作用。  相似文献   

4.
羔羊丘脑下部催产素的免疫组化定位   总被引:5,自引:1,他引:4  
采用免疫组织化学技术中的链霉素抗生物素-过氧化酶(streptaridin-peroxidase,SP)法,对羔羊丘脑下部催产素(oxytocin,OT)神经元的定位及分布进行了研究。结果表明,丘脑下部分泌OT的神经元主要分布在室旁核和视上核,在环核、视上弥散核、弓状核、室周核、穹窿周核、丘脑下部前区、丘脑下部外侧区、丘脑下部后核和乳头体各核团等也有一定数量的阳性神经元;阳性神经纤维仅见于室旁核、视上弥散核、视上核和交叉上核,在正中隆起第三脑室附近有较多数量的阳性神经纤维。观察结果提示,OT在羔羊丘脑下部分布广泛,且丘脑下部OT经神经垂体、第三脑室、血管3条途径释放,经血液循环最终作用于靶细胞而发挥生理作用。  相似文献   

5.
为研究青年期广西本地水牛催产素能神经元的表达特点,试验采用免疫组织化学技术中的PicTureTM二步法对广西本地水牛催产素神经元的定位及分布进行了研究.结果表明:下丘脑分泌催产素的神经元主要分布在室旁核、视上核和弓状核,在视前内侧核、视交叉上核、下丘脑前核、下丘脑后核、背内侧核、腹内侧核和乳头体核等核团也有一定数量的阳性神经元;阳性神经纤维仅见于室旁核、弓状核、乳头体核,在正中隆起第三脑室室管膜附近有较多数量的阳性神经纤维.观察结果提示:下丘脑催产素经神经垂体、第三脑室、血管3条途径释放;不同种属动物下丘脑催产素存在差异.  相似文献   

6.
ER免疫反应产物在幼龄公山羊下丘脑-垂体-性腺轴的表达   总被引:2,自引:0,他引:2  
应用免疫组化SP法时雌激素受体(ER)免疫反应产物在幼龄公山羊下丘脑、垂体、性腺中的分布特点进行了研究。结果显示,下丘脑中ER免疫反应阳性神经元主要分布在视上核、室旁核、室周核等9个核团,在视前区、下丘脑外侧区等核团也有一定数量的阳性神经元;阳性细胞呈圆形、卵圆形、三角形不等,阳性物质大多位于细胞质和胞核,阳性纤维散布于各阳性核团中;在正中隆起和第三脑室室管膜可见大量小而密集排列的深染的阳性神经元。神经垂体中可见大小不等、排列较均匀且染色较深的纤维,腺垂体中腺细胞呈强阳性着色。睾丸曲细精管中的初级精母细胞和支持细胞以及睾丸间质细胞中的ER阳性产物均为微弱表达。由此表明,幼龄公山羊雌激素除作用于性腺外,还主要作用于中枢神经系统的广泛区域,推测其参与了脑中生殖、内分泌、认知等多种功能的调控。  相似文献   

7.
鸡加压素(VP)免疫反应神经元分布于视上核、室旁核的中部和后部、视上交叉核、视前大细胞核、室周弓状核、下丘脑外侧核和室周核,正中隆起、视上背侧交叉和隔内侧区存在大量的VP阳性纤维末梢.在第三脑室室管膜和脑基底神经胶质板上也存在VP阳性神经元.同时发现室旁核、室周核、室周弓状核及视前大细胞核的VP阳性神经元有突起伸入到第三脑室室管膜或突出于脑室腔,视上核的VP阳性神经元也有突起投射至脑基底神经胶质板上或伸至蛛网膜下腔.据此认为,VP的释放是多途径的.  相似文献   

8.
妊娠期奶山羊下丘脑GnRH和OT免疫反应双标记细胞的分布   总被引:2,自引:0,他引:2  
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。  相似文献   

9.
本文回顾了下丘脑大细胞神经分泌系统的研究历史,并着重概述了该系统近期的形态学研究进展。视上核分为主部和交叉后部,主要成自大的、致密排列的多极神经元,多为加压素(VAS)能。其纤维主要参予形成视上垂体束,部分则投射至室旁核和正中隆起外侧带。室旁核分为5个亚部。内侧室旁核主要成自催产素(OXY)能大细胞,外侧室旁核神经元较大,VAS能细胞居中,OXY能细胞围绕于外周;背内侧帽成自中、小细胞,乏垂体后叶素能神经元;室旁核后亚核居末端,成自疏松排列的棘形大细胞,多为OXY能;小细胞部中OXY能和VAS能神经元较少。室旁核有着广泛的纤维投射,除形成室旁垂体束投射至神经垂体外,还投射至正中隆起外侧带、脊髓、脑干等。副核包括前连合核、前后弯窿周核、环核和内侧束前脑核等。  相似文献   

10.
鸡脑催乳素免疫反应神经元的分布   总被引:1,自引:0,他引:1  
运用ABC法观察了催乳素(PRL)免疫反应神经元在鸡脑的分布。结果,PRL阳性胞体主要分布在视交叉上核、视前室旁核、视上核、下丘脑室旁核、弓状核和伏隔核,旧纹状体、正中隆起存在大量阳性纤维末梢,在侧脑室腹侧的室管膜和脑基底神经胶质板上也存在PRL阳性神经元。视前室旁核、视交叉上核、下丘脑室旁核、弓状核等核团内的PRL阳性神经元有突起向第三脑室投射,伏隔核内及侧脑室室管膜上的PRL阳性神经元有突起伸至侧脑室,视上核的PRL阳性神经元也有突起投射至脑基底神经胶质板,表明鸡脑内的PRL可以释放入脑室系统,参与调节脑-脑脊液神经体液回路。  相似文献   

11.
运用免疫组化ABC法妊娠26~120d的奶山羊黄体中催产素免疫反应细胞的分布进行了观察。结果表明,奶山羊妊娠黄体中存在催产素(Oxytocin,OT)免疫反应阳性细胞。阳性细胞在形态上以卵圆形、圆形、棱形为主,还有一些具有明显的突起。根据阳性细胞胞质内反应颗粒着色的深浅,可把OT阳性细胞分为强阳性、中等阳性和弱阳性3种。在妊娠26~30d,阳性细胞数量最多,强阳性细胞主要分布于黄体的周边,中等阳性及弱阳性细胞则均匀分布于整个黄体组织中,妊娠31~60d,阳性细胞数量明显下降,弥散于整个黄体组织中;妊娠61~120d,阳性细胞的数量及逐渐增多,以中等阳性和弱阳性细胞为主,而强阳性细胞数量较少。连续切片HE染色的对照观察显示妊娠黄体中大、小黄体细胞均可出现OT免疫阳性反应。  相似文献   

12.
Neural regulation of the bovine corpus luteum   总被引:1,自引:0,他引:1  
The ovarian noradrenergic stimulation or noradrenaline (NA) administration directly to the ovary in cow increases ovarian oxytocin (OT) release and post-translational processing of OT synthesis within a few minutes has been established in both in vivo and in vitro studies. Furthermore, NA affects progesterone secretion and its synthesis by an increase of cytochrome P450scc and 3beta-hydroxysteroid dehydrogenase activity. This effect is mediated via luteal cell beta(1)- and beta(2)-receptors. Their total amount correlates with peripheral progesterone concentrations during the luteal phase and this reflects the ability of the ovary to react to beta-stimulation. On the other hand, ovarian denervation causes a decrease of steroidogenic activity in the CL, an increase of beta-receptors on luteal cells, a delay in follicular development and the disruption of cyclicity. Moreover, decrease of progesterone secretion by 20-30% was seen after brief pharmacological blockade of ovarian beta-receptors in the mid-cycle of cattle. We assume that tonic beta-stimulation of the CL ensures the basal secretion of progesterone, whereas acute noradrenergic activation supports the CL during stressful situations which could impair its function. Conversely, long-lasting increase in blood catecholamine concentrations markedly decreases the number of beta-receptors in CL, presumably due to their down-regulation. Concentrations of dopamine (DA) within the CL are highly correlated with those of NA during the estrous cycle, and are higher in the newly-formed than in the developed corpus luteum, the regressed corpus luteum or the corpus luteum of pregnant females. Bovine CL can synthesise de novo NA from DA as a precursor. Concluding, presented data indicate that noradrenergic stimulation can be an important part of mechanism supporting secretory function of CL.  相似文献   

13.
Polychlorinated biphenyls (PCBs) due to their lipophilic properties can be easily accumulated in animal and human body and elicit diverse effects causing impairment of reproductive processes. Since these compounds were not be able to affect directly the luteal steroidogenesis, the aim of the present study was to verify hypothesis that PCBs can impair the effect of LH on the secretory function of luteal cells. Bovine luteal cells from different stages of the oestrous cycle (days 1-5, 6-10, 11-15 and 16-18) were exposed for 72h to various congeners of PCBs (PCB 126, PCB 77 and PCB 153) at the doses of 1, 10 or 100 ng/ml, in the presence or absence of LH (100 ng/ml), to determine the possible effect of these compounds on progesterone (P4) and ovarian oxytocin (OT) secretion. Only PCB 77 on days 1-5 and 16-18 increased P4 secretion. All PCBs decreased LH-simulated secretion of P4 from luteal cells obtained from all days of luteal phase. Dioxin-like congener (PCB 126) inhibited (P<0.05) the most evidently LH effect on P4 secretion. All congeners, except the lower doses of PCB 126, increased (P<0.05) OT secretion. They can also increase LH-stimulated secretion of OT, but the effect was dependent on the congener used and on the phase of oestrous cycle. On days 1-5 and 10-15, PCB 126 diminished LH-stimulated effect on OT secretion from luteal cells. PCB 77 (mimickig both dioxin and estradiol effect) in the higher doses, amplified effect of LH-stimulated OT secretion, while on all other days it diminished LH influence. PCB 153, which has estrogen-like properties, amplified LH effect on OT secretion during all studied days of the cycle. We conclude that PCBs (supposedly via estrogen and arylhydrocarbon - AhR receptor) may directly affect LH-stimulated function of CL. This does not appear to be a direct adverse effect on luteal steroidogenesis, but rather indirect on OT secretion from or within CL.  相似文献   

14.
15.
Factors which induce the corpus luteum persistent (CLP) creation in animal ovaries are located in the hypothalamic-pituitary-ovarian axis and also in the uterus. In cows and likewise in others animals, various mediators of inflammatory reaction are released, mainly proinflammatory cytokines from inflamed uterus into the blood and lymph. Afterwards the cytokines cross the blood-brain barrier, and though the brain mediators alter the hormonal profile and amplitude pulses of the hormones release in the hypothalamus and the pituitary. Until it is known, that cytokines: IL-1, IL-2, IL-6, TNF-alpha and also IFN-alpha, administered into the median eminence, cause an increase in corticotrophin-releasing hormone (CRH) and adrenocorticotropic hormone (ACTH) concentrations and decrease in the pituitary gland hormones secretion. The immune system, represented in the corpora lutea (CL) by numerous macrophages/monocytes, limphocytes and neutrophils plays an important role in the luteolysis process. The stimulating factor of the infiltration of these cells is an increased PRL level. The preovulatory increase in PRL level regulates the number of macrophages in newly-formed CL and later influences the number of these cells in the luteolysis period. The pulsatory release and high levels of the hypophyseal oxytocin (OT) and uterine PGF2alpha ensure the beginning and the normal course of the luteolysis period. The cytokines decrease OT concentration and disorder its pulsatory release from the pituitary. In these circumstances the quantity of the uterine PGF2alpha reaching ovaries, is insufficient to begin luteolysis. In the inflamed uterus, the elevation of PGE2 and PGI2 synthesis takes place. Both prostaglandins cause smooth uterine muscles relaxation and the dilatation of blood and lymph vessels in this organ. In these conditions, the blood and lymph outflow from the uterus is several times slower than in the control animals. The secretion of P4 and E2 from CLP, in comparison with control animals, is significantly lower. Decreased P4 concentration during the luteal phase of the estrous cycle, and E2 in the initiation of the luteolysis period, may cause the insufficient preparation of the endometrium for hypophyseal OT activity. Finally, we can assume that the creation of the CLP in the animal ovary is an exceptionally complex and not yet fully understood process.  相似文献   

16.
Effect of polychlorinated biphenyles (PCBs) on viability and secretory function of luteal and granulosa cells from mature cows was studied. Luteal cells from corpora lutea of different developmental stages and granulosa cells from follicles of >1 cm< in diameter were used. Neither individual congeners (PCB-126, -77, -153) nor mixture of PCBs Aroclor Ar) 1248 at the dose of 1, 10 or 100 ng/ml affected the viability of cells (P>0.05) compared to control after 72 h of incubation. PCBs markedly increased (P<0.05-0.001) oxytocin (OT) secretion from granulosa cells. This effect was the most evident when granulosa cells from follicles <1 cm diameter was treated with PCB-77 which is assumed to stimulate both arylhydrocarbon receptor (AhR) and estradiol (E2) receptor. Even the lowest dose of this compound (1 ng/ml) outranged the effect produced by cortisol (10(-5)M) used as positive control. There was marked effect (P<0.05-0.001) of PCBs on luteal cells from days 6-15 of the estrous cycle. However, influence of PCBs on OT secretion from luteal cells on day 1-5 and 16-18 of the estrous cycle was less evident. Again, PCB-77 was the most efficient stimulator of OT secretion. While the lowest effect was found after treatment of cells with PCB-126 which has dioxin-like properties. It can be assumed that diverse effect of PCBs on female reproduction largely results from the influence of these compounds on ovarian OT secretion. Since both synthesis and secretion of ovarian OT in bovine do not markedly depend on estradiol, some alternative cellular pathways of PCBs on ovary function are suggested.  相似文献   

17.
用HRP追踪法、高尔基技术和免疫组化方法研究了鸡第三脑室接触脑脊液神经元的结构、分布和化学性质.结果证实,鸡第三脑室的接触脑脊液神经元主要分布在室旁器、乳头体隐窝、漏斗隐窝顶壁和侧壁的室管膜,散在于室周区、室旁核、视前大细胞核以及弓状核.接触脑脊液神经元可分为4种类型:室管膜上神经元、室管膜内神经元、室管膜下神经元和远位神经元.这些神经元含有神经肽——VP和OT.提示第三脑室接触脑脊液神经元有直接释放OT和VP的功能.  相似文献   

18.
The corpora lutea (CL) are endocrine glands that form in the ovary after ovulation and secrete the steroid hormone, progesterone (P4). P4 plays a critical role in estrous and menstrual cycles, implantation, and pregnancy. The incomplete rodent estrous cycle stably lasts 4–5 days and its morphological features can be distinguished during each estrous cycle stage. In rat ovaries, there are two main types of CL: newly formed ones due to the current ovulation (new CL), and CL remaining from prior estrous cycles (old CL). In the luteal regression process, CL were almost fully regressed after four estrous cycles in Sprague-Dawley rats. P4 secretion from CL in rodents is regulated by the balance between synthesis and catabolism. In general, luteal toxicity should be evaluated by considering antemortem and postmortem data. Daily vaginal smear observations provided useful information on luteal toxicity. In histopathological examinations, not only the ovaries and CL but also other related tissues and organs including the uterus, vagina, mammary gland, and adrenal glands, must be carefully examined for exploring luteal changes. In this review, histological and functional characteristics of CL in rats are summarized, and representative luteal toxicity changes are presented for improved luteal toxicity evaluation in preclinical toxicity research.  相似文献   

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