DEVELOPMENT OF ABERRANT CRYPT FOCI INVOLVES A FISSION MECHANISM AS REVEALED BY ISOLATION OF ABERRANT CRYPTS

Morphological analysis of isolated colonic crypts in rats, postnatally , indicated that the crypts reproduce themselves by a fission mechanis m, the division beginning at the crypt base and proceeding upwards unt il there are two separate crypts. Occasionally, before the separation is complete, a second fission process starts on one or both sides of a bifurcating crypt and a triple-branched or quadruple-branched crypt r esults. Analysis of isolated aberrant crypt foci (ACF) in rats treated with 1,2-dimethylhydrazine revealed that the development of ACF consi sting of multiple crypts is also due to a fission mechanism. Initially , an indentation appears at the base of a single ACF crypt, with subse quent formation of a bifurcation and eventual crypt division.