Lack of restoration in vivo by K+-channel modulators of jejunal fluid absorption after heat stable escherichia coli enterotoxin (STa) challenge

Abstract

Enhanced potassium ion permeability at the enterocyte basolateral membrane is assumed to facilitate sustained chloride ion and fluid secretion into the intestinal lumen during episodes of secretory diarrhoeal disease. To examine this concept in vivo, two potassium ion channel blockers and a channel opener were coperfused with E. coli heat stable STa enterotoxin to determine whether such compounds improved or worsened the inhibited fluid absorption. In the STa (80ng/mL) challenged jejunal loop, the fluid absorption rate of 28.6 ± 5.8 (14)μL/cm/hr was significantly below (P