HISTOGENESIS OF THE HUMAN TESTES / 解剖学报

ABSTRACT

Testes of 35 human fetuses from 7-week gestation to newborn were studied. The testes were fixed in Carnoy's solution and stained with HE,Unna's method for RNA and McManus PAS reaction for glycogen. In 7-week old embryo(CRL 18mm),the gonad shows no morphological indication of sex,and still is indifferentiated.In the 13-week embryo,the basic structural of the testis such as thickened fibrous tunica albuginea,prominent sex cords and accumulative interstitial cells are clearly identifiable. The sex cords are now called testicular cords which were composed of primordial germ cells and supporting cells.The cords lumen appeared at 14.5-week of gestation and the germ cells in the cords are distinguished by the size of cell bodies,contain- ing a large amount of glycogen and large round nuclei with conspicuous nucleoli. The eosinophil accumulative interstitial cell(Leydig cell)may be divided into 3 typesinmature,mature and degenerating.In the 20-week embryo the number of the interstitial cells decreased sharply.