Sister chromatid exchange analysis in the colonic and small intestinal epithelium of the mouse

This report describes a method which produces high quality chromosome preparations from the colon and the small intestine of the mouse. These preparations are suitable for sister chromatid exchange (SCE) analysis because the pretreatment used to dissociate the cells does not prevent sister chromatid differentiation and because very little tissue handling is required at the time of killing, thus allowing sampling from several animals within a short period of time. Since the procedure used to make chromosome preparations from the tissue samples is very simple, no cytogenetic experience is required to make excellent chromosome preparations using this method. To demonstrate the utility of this method, the induction of SCEs by cyclophosphamide was measured in small intestine and colon samples collected from the same animals. The results indicate that this method can be used to determine dose responses in both tissues.