Administration of anti-asialo GM1 serum increases aberrant crypt foci induced by 1,2-dimethylhydrazine in the large bowel of rats.

We investigated the influence of the administration of anti-asialo GM1 antibody on aberrant crypt foci (ACF) formation induced by a single injection of 1,2-dimethylhydrazine (DMH). At four weeks after the injection of DMH (20 mg/kg body weight), the number of ACF and aberrant crypts were counted. Most ACF appeared in the distal large bowel, accounting for approximately 60% of the total ACF in both groups. Rats administered anti-asialo GM1 had significantly more ACF in the distal colon, the rectum and the total large bowel as compared to control rats. A similar tendency was observed for the number of aberrant crypts. The increased number of ACF resulting from the administration of anti-asialo GM1 was not accompanied by the enlargement of ACF size in every part of the colon. This study demonstrated that the administration of anti-asialo GM1 at the initiation stage leads to an increase in ACF as well as aberrant crypts in the distal colon, rectum and total large bowel probably via the suppression of natural killer cells.