摘要
本研究采用石蜡切片、Nissl染色、H-E染色及免疫组织化学SuperPicTure~(TM)二步法检测5头广西摩拉杂交母水牛的下丘脑、垂体和卵巢中促性腺激素释放激素(GnRH)的分布情况,旨在研究GnRH在下丘脑、垂体及卵巢的分布上的联系,进而了解GnRH在下丘脑、垂体及卵巢三者之间分泌释放途径,为进一步研究GnRH的合成和作用机制提供形态学依据,并对广西摩拉杂交水牛的繁殖育种起到一定的参考指导作用。试验结果显示:广西摩拉杂交水牛下丘脑GnRH免疫阳性神经元大小差异不显著,细胞直径变化不大。GnRH免疫阳性神经元主要分布于视前内侧核、视上核、室旁核、视前外侧核,其次是背内侧核、视交叉上核、前核、弓状核、后核,腹内侧核及乳头体核,而正中隆起分布最少。视上核的GnRH免疫阳性神经元最为密集,阳性神经元出现率为27.88±13.37,而视前外侧核的神经元最为疏松,阳性细胞出现率最低,为11.69±4.43。正中隆起的GnRH免疫阳性产物灰度值最高,为135.24±16.32,表明正中隆起GnRH免疫阳性反应最强,而背内侧核的灰度值最低,为171.17±26.93。GnRH免疫阳性纤维只分布于正中隆起、弓状核、室旁核和乳头体核,尤以正中隆起最多,而在其他核团没有发现GnRH免疫阳性纤维。在第三脑室附近及乳头体核的毛细血管发现有GnRH免疫阳性神经元及GnRH免疫阳性纤维。广西摩拉杂交水牛的神经垂体未发现有GnRH免疫阳性产物,只在腺垂体远侧部发现有GnRH免疫阳性细胞,细胞以弱阳性为主,平均灰度值为175.78±16.73。在卵巢中发现GnRH免疫阳性产物存在于卵巢生殖上皮细胞、颗粒细胞和黄体细胞,且在黄体中发现有少量的带细小突起的GnRH免疫阳性细胞。结论:首次发现GnRH存在于广西摩拉杂交水牛下丘脑-垂体-卵巢轴的各个环节。首次发现广西摩拉杂交水牛下丘脑中各主要核团都有GnRH免疫阳性神经元的分布,尤其以视上核、视前核、室旁核分布最多。首次发现GnRH免疫阳性产物只存在广西摩拉杂交水牛的腺垂体中。首次在广西摩拉杂交水牛卵巢中生殖上皮细胞、颗粒细胞和黄体细胞发现有GnRH免疫阳性产物。
To study the association of gonadotropin releasing hormone(GnRH)'s distribution in hypothalamatic、pituitary and ovary,and understand how the GnRH secrete releasing in hypothalamus、hypophysis and ovaries,the paraffin section、Nissl staining、H-E staining and immunohistochemistry SuperPicTure~(TM)two step method were used to detect the distribution of GnRH in hypothalamatic-pituitary-ovary axis of five femal Guangxi murrah hybrid water bufflos.The test results could provide morphology according to study the GnRH's synthesis and mechanism of action,and could play reference and directions part in breeding Guangxi murrah hybrid water bufflo.The test results display:the GnRH immunoactive neuron sizes weren't significant difference,and the cells' diameters were change little.The GnRH immunoactive neurons were main distributed in medial preoptic nucleus、supraoptic nucleus、paraventricular nucleus and lateral preoptic nucleus,next in dorsomedial nucleus、suprachiasmatic nucleus、anterior hypothalamic nucleus、arcuate nucleus、posterior hypothalamic nucleus、ventromedial nucleus and mamillary nucleus,and distributed least in median eminence.The GnRH immunoactive neurons of supraoptic nucleus were most conferted,the average frequency of immunoaetive neuron was27.88±13.37,and lateral preoptic nucleus' neurons were most lax,the average frequency of immunoactive neuron was lowest, 11.69±4.43.The average gray scale of GnRH immunoactive production of median eminence was highest,135.24±16.32,indicated that GnRH immunity positive reaction was most powerful in median eminence,and the dorsomedial nucleus average gray scale was lowest,only 171.17±26.93.The GnRH immunoactive fibers were only distributed in median eminence、arcuate nucleus、paraventricular nucleus and mamillary nucleus,especially most in the median eminence,and other nucleus didn't discover the GnRH immunoactive fibers.There were GnRH immunoactive neurons and GnRH immunoactive fibers in nearby the third ventricle and mamillary nucleus' blood capillary.In Guangxi murrah hybrid water bufflos hypophysis,the GnRH immunoactive productions were only discoved in the pars distalis hypophyseos,and not discoved in the neurohypophysis,the GnRH immunoactive cells of the pars distalis hypophyseos were main weakly positive,the average gray scale was 175.78±16.73.In ovaries,GnRH immunoactive productions were distributed in the germinal epithelium cells、granulosa cells and Iutein cells,and a few GnRH immunoactive cells with small prominence were discovered in corpus Iuteum.Conclusion:The GnRH was first discovered in singulorum link of hypothalamatic-pituitary-ovary axis of Guangxi murrah hybrid water bufflo.The GnRH immunoactive neurons were first discovered in every main nucleus of Guangxi murrah hybrid water bufflo hypothalamus,especially distributed in supraoptic nucleus、preoptic nucleus、paraventricular nucleus most.The GnRH immunoactive productions were first discovered only in Guangxi murrah hybrid water bufflo adenohypophysis.The GnRH immunoactive productions were first discovered in the germinal epithelium cells、granulosa cells and lutein cells of Guangxi murrah hybrid water bufflo.
引文
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