Respiration and oxidation of various substrates by ileum in vitro

¹ U. S. Naval Medical Research Unit No. 2 (NAMRU-2), Taipei, Taiwan, Republic of China

The respiration of ileum from the rabbit, monkey, hamster, guinea pig, and rat in vitro was studied. Measurements were also made of the rate of oxidation of labeled glucose, glutamine, acetate, and palmitate to C¹⁴O₂ by ileum in these species. Added glutamine and acetate are oxidized at a faster rate than added glucose by rabbit ileum. The guinea pig and monkey ileum gave values similar to the rabbit except that the guinea pig tissue had a higher rate of respiration. The hamster and rat ileum both oxidized glutamine and glucose at nearly the same rate. All species oxidized acetate vigorously. All species oxidized labeled palmitate which was added at low concentrations. Mucosal cells of rabbit ileum oxidized the various substrates at rates that were proportional to full-thickness ileum. It is concluded that ileum from various species of animals can oxidize a number of different substrates in vitro. There are differences in rates of oxidation by various species.

Key Words: oxidation of glucose • glutamine • glutamate • palmitate • acetate • intestinal metabolism • ileum

Submitted on October 19, 1964