[The indirect roles of microtubules in the nuclear morphogenesis of spermatids].

The depolymerization of the microtubules of the spermatid manchette was effective for 4 to 5 h in rat, starting 30 min after one intratesticular injection of colcemid in vivo. The manchette built up again later was normal in old elongating spermatids but very oddly shaped in young elongating spermatids in which the nuclear shape was abnormal and the relations between the nucleus and the endoplasmic reticulum aberrant, ie destruction of the apparatus for nucleocytoplasmic exchange. From 24 to 96 h after the injection, a progressive shifting of the cellular associations indicated that young spermatids elongating at the time of injection did not differentiate further. This could result from the lack of two roles not played by the new manchette: the guiding effect of the intranuclear chromatin and the role of skeleton for the cytoplasmic apparatus devoted to nucleocytoplasmic exchange. Step 14 to 16 spermatids were not modified by the removal of the manchette due to correct reformation of a typical manchette 4 to 5 h later. The associations of the microtubules and the nuclei and the speculative roles of the microtubules during spermiogenesis have been discussed.