[The formation process of chromatoid body in spermatogenic cell of teleost, Spinibarbus caldwelli (Nichols)].

The formation process of chromatoid body in spermatogenic cell of teleost, Spinibarbus caldwelli (Nichols) was observed with electron microscopy. The chromatoid body was formed in the primary spermatogonium. First, the precursor of chromatoid body adhered to the inner surface of the nuclear envelope. The nuclear envelope where the chromatoid body adhering was destroyed. At the inner side of the precursor of chromatoid body, new nuclear envelope formed. It separated the precursor of chromatoid body from nucleus. The newly formed nuclear envelope was concaved. Thus a hollow appears on the surface of the nucleus. The precursor of chromatoid body gathered in the hollow and condensed into chromatoid body. There were many big gaps on the newly formed nuclear envelope. A little precursor of chromatoid body which had not been separated from the nucleus before comed out of the nucleus through these gaps and into the hollow, where it integrated with the chromatoid body. The way of chromatoid body formation in spermatogenic cell of Spinibarbus caldwelli was different from the way by which nuclear material comes out of the nucleus. It was suggested that there was a different way by which nuclear material could go out of the nucleus. The chromatoid body combined with mitochondria soon after it was formed, and left the hollow. During the development of the spermatogonium, the chromatoid body separated from mitochondria.