Enterocyte respiration rates in feline small intestine exposed to graded ischemia

The purpose of our study was to investigate the changes in enterocyte cellular and mitochondrial respiration rates subsequent to ischemia of graded duration. The small intestine of anesthetized adult cats was assigned to one of five treatment regimens: control or ischemia of 15-, 30-, 60-, or 90-min duration. Cellular and mitochondrial respiration was measured using a Clark-type O2 electrode at 0 and 4 h postharvest. Ischemia of increasing duration caused a progressive decrease in cellular and mitochondrial respiration in enterocytes at 0 h postharvest. By 4 h postharvest, cellular and mitochondrial respiration rates for the 15-, 30-, and 60-min ischemic groups had recovered to near control levels, whereas the 90-min group showed minimal recovery. These data suggest that ischemia suppresses cellular and mitochondrial respiration of intestinal epithelial cells, the magnitude of which is related to the ischemic duration. The ischemia-induced suppression in cellular respiration primarily reflects a reduction in mitochondrial respiration.