RELATIONSHIP BETWEEN THE NATURE OF MUCUS AND CRYPT MULTIPLICITY IN ABERRANT CRYPT FOCI IN THE RAT COLON

Aberrant crypt foci (ACF) induced in the distal colon of F344 male rat s, 4, 8, 12 and 35 weeks after the first administration of 1, 2-dimeth ylhydrazine-2HCl (DMH) were examined to determine whether a correlatio n exists between the nature of goblet cell mucin and the number of cry pts (crypt multiplicity) comprising the ACF. According to the ACF scor e calculated from the results of the qualitative observation of sulfom ucins (SuMs) and sialomucins (SiMs), the ACF in the 4th week showed a weak correlation between the nature of the mucus and crypt multiplicit y, and the ACF of each class showed similar mucous profiles. From the 8th week, a significant difference (P < 0.01) was recognized between t he ACF consisting of 3 crypts or less and those consisting of 4 crypts or more. The proportion of crypts with SiM predominance showed a decr ease in the 8th week in the ACF consisting of 1 crypt and in the 12th week in the ACF consisting of 2 or 3 crypts, implying a recovery tende ncy. The ACF consisting of more than 4 crypts showed little change ove r time, retaining the tendency of SiM predominance. Ulex europaeus agg lutinin-I (UEA-I) lectin-positive crypts appeared in the ACF. This fin ding was significantly more prominent (P < 0.001) in the ACF with SiM predominance than in the ACF with Surd predominance at each experiment al period, and in the 12th week after the first administration of DMH, the incidence of ACF with UEA-I-reactive mucin was decreased in the A CF groups consisting of 3 crypts or less, compared with the ACF groups consisting of 4 or more crypts, These results suggest that the biolog ical quality of mucus in ACF consisting of 4 or more crypts is differe nt from that in ACF consisting of 3 crypts or less. This difference sh ould be considered when ACF are used as an intermediate biomarker of c olon cancer.