INTESTINAL ABSORPTION AND TRANSPORT IN THYONE. II. OBSERVATIONS ON SUGAR TRANSPORT

¹ Marine Biological Laboratory, Woods Hole, Massachusetts and Department of Physiology, Rutgers University, New Brunswick, New Jersey 08903

In the first paper of this series the biological background for the study of absorption and transport of sugars in the intestine of Thyone was presented. In this paper, physiological parameters which affect the absorption of glucose such as the nature of the incubation medium, the effect of pH, the net flux of water, and the effect of starvation under captivity have been studied.

The capacity for glucose absorption by different regions of the intestine was investigated under in vitro and in vivo conditions. The first loop is the main site for the absorption and transport of sugar and the clear zone of the intestine provides the reserve capacity for absorption during continuous feeding.

The in vivo studies demonstrate that the intestinal tissue acts as the first storage site for the absorbed sugar. Only 3-17% of the glucose absorbed is rapidly transferred into the perivisceral fluid for distribution to other organs. The hemal sinuses are not effectively involved in the distribution of absorbed glucose. The perivisceral fluid is the functional circulatory fluid.