Accumulation of vitamin A by small intestine of the rat in vitro

¹ Institute of Human Nutrition, Prague-Kr, Czechoslovakia

The vitamin A accumulation by the small intestine of the rat was investigated, using the method of everted intestinal sacs as modified by the authors. For incubation, modified Krebs-Ringer bicarbonate buffer with vitamin A-acetate stabilized with human albumin was used. Vitamin A accumulates in the intestinal wall and the kinetics of this process are analogous to the Michaelis-Menten kinetics. Accumulation is inhibited by KCN and NaF. The transfer of vitamin A into the serosal contents of sacs was minimal. There were no significant differences in the accumulation of vitamin A in various parts of small intestine. It is concluded that the accumulation of vitamin A has a complex and active character.

Note:
With the Technical Assistance of J. Havlíková

Key Words: active transport • absorption of vitamin A • jejunoileal absorption gradient

Submitted on November 13, 1962