Differential staining of dysplastic aberrant crypt foci in the colon facilitates prediction of carcinogenic potentials of chemicals in rats.
We developed a novel and simple method to identify dysplastic aberrant crypt foci (ACF) induced in rats by colon carcinogens more efficiently and selectively without conducting laborious histological examination, which usually requires enough time to get final diagnosis. By adding a simple decolorization process with 70% methanol after conventional 0.2% methylene blue staining, dysplastic ACF could be differentially contrasted. To examine the validity of this novel method, which we refer to as differential staining, we analyzed colonic lesions induced by three heterocyclic amines, including 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine, and found that the number of dysplastic ACF detected more precisely reflected their carcinogenic potential than the total numbers of ACF.
Ochiai
Masako
M
Biochemistry Division, National Cancer Center Research Institute, 5-1-1, Tsukiji, Chuo-ku, Tokyo 104-0045, Japan.
Watanabe
Masatoshi
M
Nakanishi
Masako
M
Taguchi
Ayako
A
Sugimura
Takashi
T
Nakagama
Hitoshi
H
D000818:Animals; D015197:Carcinogenicity Tests / Q000379:methods*; D002273:Carcinogens; D003110:Colonic Neoplasms / Q000139:chemically induced*; D007093:Imidazoles; D008297:Male; D008751:Methylene Blue; D011230:Precancerous Conditions / Q000139:chemically induced* / Q000175:diagnosis; D051381:Rats; D011916:Rats, Inbred F344; D013194:Staining and Labeling
D002273:Carcinogens; D007093:Imidazoles; C049584:2-amino-1-methyl-6-phenylimidazo(4,5-b)pyridine; D008751:Methylene Blue