DETECTION METHOD OF CARCINOGENIC PROMOTER

PURPOSE:To detect a carcinogenic promoter by a method wherein an RDS- nonionducible cell nucleus is dyed with a pigment displaying a coloring action which is different from color development by an immunity-tissue chemical technique and RDS-inducible cells are discriminated from RDS-noninducible cells and counted. CONSTITUTION:A tissue which has been extracted is subjected properly to, e.g. a fixation treatment, dehydrating treatment, a degreasing treatment, a paraffin color embedding treatment, a thin-section specimen formation treatment ore the like, After that, the tissue is dyed with BrdU by an immunity-tissue chemical technique. Thereby, only cells which have been labeled with the BrdU are dyed. Then, the tissue is dyed with a dyestuff displaying a coloring action which is different from' the coloring action by being dyed with the BrdU. By this dying operation, the cell nucleus of a cell which has not been labeled with the BrdU is dyed. Since the tissue which has been dyed in this manner is dyed by differentiating its color by using different dyestuffs, RDS-inducible cells can be discriminated from RDS-nonconducible cells by using a microscope as required and can be counted. On the basis of this counted result, it can be judged whether a substance to be tested is a carcinogenic promoter or not.