Total colectomy interferes with nutrient absorption in the small intestine in rats

Abstract

The main function of the colon is water and electrolyte absorption. Total colectomy eliminates this colonic function and may alter the absorptive capacity of the small intestine. This study determines the effects of total colectomy on glucose absorption in the jejunum and examines whether functional adaptation occurs in the small intestine. Total colectomy with ileo-rectal anastomosis was performed on anesthetized adult Sprague-Dawly rats. Sham rats were identically handled without resection of the colon. Rats were allowed to recover for a minimum of 2 weeks. Glucose absorption was determined by in vivo single-pass perfusion. Jejunal segments were perfused with a modified Ringer solution containing radiolabelled glucose and phenol red as a nonabsorbable marker. Glucose (20 mM) absorption was determined 2 weeks and 1 month post surgery. Glucose absorption significantly increased from 3.24 ±0.06 μmol/60min-cm to 4.35±0.09 (n = 5) for the first hour and from 1.89±0.14 to 2.94±0.15 (n = 5) for the second hour in 2 weeks-colectomized rats. One month after surgery, glucose absorption returned to normal (3.75±0.12 in sham vs 4.12±0.19 for the first hour; 3.77±0.05 in sham vs 3.87±0.36 for the second hour). Our results show that total colectomy increased glucose absorption in the jejunum. This may be due to an increase in sodium absorption to compensate for its loss in the colon, thus coupling it to glucose transport.