Study of the cellular turnover in the small intestine of the lactent Didelphis albiventris.

A 1% trypan blue aqueous solution, buffered to pH 7.3, orally administrated was used as a tracer in an attempt to establish the cellular turnover in the small intestine epithelium of the lactent marsupial Didelphis albiventris. The complex trypan blue-milk albumin was captured by the cells lining the proximal, medium and distal segment of small intestine, differing from the rodents which are unable to absorb the dye by endocytosis at the level of the proximal small intestine. A complete cellular turnover was observed in the proximal small intestine 7 d after treatment, whilst in the medium and distal segments 8 d were required for the turnover to be completed.