Colonic absorption of bacterially synthesized vitamin K2 in the rat.

Colonic absorption of bacterially synthesized vitamin K2 ([3H]menaquinone-9) was studied with everted rat colonic sacs in vitro. The mean +/- SE rate of absorption of the vitamin by the colon was 20 +/- 1.45 pmol/min per 100 mg tissue at 300 nM mucosal concentration of the vitamin.

Mechanism and site of small intestinal absorption of alpha-tocopherol in the rat.

The site and mechanism of alpha-[5-methyl-3-H]tocopherol absorption was investigated using everted rat small bowel sacs incubated in a micellar medium. Mean plus or minus SE absorption rates of the vitamin at 300 muM incubation solution concentration by proximal, medial, and distal small bowel segments were 2.2 plus or minus 0.