Mode of rat cecal enlargement induced by a short-term feeding on glucomannan.

The increase in wet weight of rat cecum was evident at 16 hr of glucomannan ingestion and continued until 184 hr (the longest period observed in this experiment), reaching about 2.5-fold. The ratios of total protein/DNA and RNA/DNA were both always higher in cecum of rats fed glucomannan than the control group (0 hr). During the initial 40 hr, no significant change in total DNA content was observed with the increase in total protein and RNA. Furthermore, the incorporation rate of [3H]thymidine in cecal DNA was even lower in the glucomannan feeding than the control (0 hr) during the initial 40 hr. After 88 hr of the experiment, however, a significant increase in the synthetic rate of DNA was found as well as [14C]leucine incorporation into total protein. It was discussed that a hypertrophic change in rat cecum was initially induced by glucomannan ingestion and was followed by hyperplastic growth under continuous exposure of glucomannan.