Meeting Abstract

66.5  Jan. 7  Intestinal hydrolase activity of the Burmese python, Python molurus COX, C.L.*; SECOR, S.M.; University of Alabama; University of Alabama clcox@bama.ua.edu

For the Burmese pythons, the dramatic postprandial upregulation of intestinal nutrient uptake is predictably matched with concurrent upregulation of intestinal hydrolase activity. Therefore we measured from the Burmese python the postprandial response of the activity of two brush border enzymes, aminopeptidase-N (APN) and maltase, from five sites of the small intestine. Intestinal mucosal samples were collected from fasted snakes, and snakes 0.25, 0.5, 1, 2, 3, 4, 6, 10, and 15 days following consumption of rat meals equaling 25% of body mass. Mucosal samples were assayed for APN activity using l-leucyl-naphthylamide (LNA) as the substrate, and maltase activity using maltose as the substrate. APN activity peaked at three days postfeeding (5-fold of fasted levels) and returned to fasted levels by day 10. APN activity was highest in the proximal four fifths of the intestine, with the distal one fifth exhibiting notably lower activities for all time-points. APN capacity, defined as the summed ability of the small intestine to hydrolyze LNA, peaked at three days postfeeding at more than 10-fold of fasted capacities, and returned to fasted levels by day 15. Maltase activity was undetected in fasted animals, and increased to barely detectable levels at two days postfeeding. The concomitant postprandial upregulation of intestinal morphology, nutrient transport rates, and enzyme activities illustrate for the python the matched regulation of their intestinal performance.