Merchant-Larios H
J Reprod Fertil Suppl. 1979(27):479-85.
The establishment and sexual differentiation of the gonads of horse embryos were studied using high-resolution techniques. The most dramatic observation is the early cytodifferentiation of the somatic cells into steroidogenic cells which takes place before sexual differentiation of the gonads. A unique morphogenetic pattern is established during this process: the seminiferous cords of the testis are completely segregated from the steroidogenic tissue by a basal lamina, while in the medulla of the ovary, steroidogenic cells differentiate inside the epithelial cords which contain germ cells. This early difference in the topographical distribution of steroidogenic cells favours the hypothesis that the interactions between somatic and germ cells vary with the genetic sex. The possibility of finding qualitative differences in steroidogenesis before and during sexual differentiation of the gonad suggests the horse gonad as a good model for the study of the role of the steroid hormones in the sexual differentiation of the mammalian gonad.
利用高分辨率技术对马胚胎性腺的建立和性别分化进行了研究。最引人注目的观察结果是，在性腺性别分化之前，体细胞就早期分化为类固醇生成细胞。在此过程中建立了一种独特的形态发生模式：睾丸的生精索通过基膜与类固醇生成组织完全分离，而在卵巢髓质中，类固醇生成细胞在上皮索内分化，上皮索中含有生殖细胞。类固醇生成细胞在地形分布上的这种早期差异支持了这样一种假说，即体细胞与生殖细胞之间的相互作用因遗传性别而异。在性腺性别分化之前和期间发现类固醇生成存在质的差异，这表明马性腺是研究类固醇激素在哺乳动物性腺性别分化中作用的良好模型。
