Molecular biological analysis of ontogenetical expression of inhibin in horse testis.

从形态学、组织化学、免疫组化、超微结构和分子生物学等方面研究了马精巢的发育变化，发现马精巢的精子发生始于2岁春季，至9岁时精子发生活性呈倒置趋势。马睾丸发育过程中最具特征的特征是色素细胞的出现和消失。这些细胞首先出现在3日龄的小马，并逐渐增加的体积，直到1岁。细胞数量在2月龄时达到最大值，随后逐渐减少，3岁后完全消失。免疫组化结果表明，在Lydig细胞和Sertoli细胞中均可见α-、βA-和β B-亚基。但是他们的强烈的恐惧感 ...更多信息 原位杂交采用地高辛标记的细胞内RNA探针，检测细胞内α-、βA-和β B-亚基的mRNA水平。在睾丸间质细胞和生精上皮的基底区检测到α、βA和β B亚基的信号。虽然由于该方法的局限性，不能在曲细精管的基底区确定信号的精确定位，但支持细胞的可能性最大。但不能排除精原细胞。在产前和产后阶段，甚至在成年马中，这些结果基本上是相似的。结果表明，Sertoli细胞和Leydig细胞均表达α亚基、βA亚基和β B亚基，且Leydig细胞的表达量高于Sertoli细胞。本研究还提示，睾丸间质细胞是马精巢中激活素和/或β-谷氨酰胺的主要来源。抑制素和（或）激活素可能通过自分泌和（或）旁分泌的方式对睾丸功能发挥调节作用，但其具体作用尚不清楚。少

Ontogenetical changes of horse testis were examined morphologically, histochemically, immunohistochemically, ultractructurally and molecular biologically with special reference to expression of inhibin α-, βA-, βB-subunits.Spermatogenesis initiated in the spring of 2 years old, and spermatogeneic activity appeared to inverase with age up to 9 years old. The most characteristic feature during development of horse testis is the appearance and disappearance of pigmented cells. These cells first appeared in 3-day old colt and gradually increased in volume up to 1 year old. The number of cells reached maximum at 2 months old, graduelly decreased, and completely disappered after 3 years old. According to their histochemical and ultrastructural feature, the pigmented cells might be macrophages phagocytized fetal types of Leydig cells.Immunohistochemically, inhibin α-, βA- and βB-subunits were found not only in Lydig cells but also in Sertoli cells, respectively. But their intensities of posit … More ive stainings were more intense in Lydig cells than in Sertoli cells.For in-situ hybrldization, digoxigenin-labelled comprementary RNA probes were prepared to detect intracellular messenger RNAS of inhibinα-, βA- and βB-subunits. Signals for inhibin α-, βA- and βB-subunits were detected in Leydig cells and the basal region of seminiferous epithelium. Although exact localization of the signals were could not identified in the basal region of the seminiferous tubules due to the limitation of this method, it may well be that Sertoli cells have the highest possibility. However we could not excluded the spermatogonia. During prenatal and postnatal stages and even in adult horses, these seults are fundamentally similar. The present results suggested that inhibin α-subunit and inhibin/activin βA- and βB-subunits were expressed not only in Sertoli cells but also in Lydig cells, and the expression level was higer in Leydig cells than in Sertoli cells. Furthermore this study suggested that Leydig cells are the major source of inhibin and/or activin in horse testis. Inhibin and/or activin may play reguration role of testicular function by autocrine and/or paracrine manner, but they are not known in detail. Less