Vincristine induced ultrastructural alterations of cardiac and smooth muscles in mice

A morphological analysis of the effect of vincristine (VCR) on the cardiac muscle and smooth muscles of blood-vessels and alimentary canal of mice has been carried out. These animals show a high resistance to sublethal doses of VCR. The changes in the cardiac muscle involve mitochondria. The widening of the space between the intercalated discs is seen and accompanied by the occurrence of spheromembranous bodies (SMB) in it. The only alteration typical of the effect of VCR in the smooth muscles is the presence of SMB inside the mitochondria. The number and extent of changes observed increased in course of experiment.