Active transport of sugars in tortoise intestine

The tortoise intestine capability for active transport of sugars has been studied in vitro at 30 degrees C, using labelled sugars. A release of glucose from the glycogen stores of the intestinal wall to the medium took place throughout the incubation period of the sacs. An active transport of 14C-D-glucose against a concentration gradient from the mucosal to the serosal compartment was evident, whereas no such activity could be detected for 14C-D-galactose. The tissue oxygen uptake was 36% higher with glucose than with galactose in the medium.