TRANSPORT OF WATER AND ELECTROLYTES BY ROTAVIRUS-INFECTED MOUSE INTESTINE - A TIME COURSE STUDY

The movement of water and transport of Na+ and Cl by mid-small intestine (M-SI) of rotavirus-infected neonatal mice was investigated by an in vitro perfusion technique. The concentrations of Na+, K+, and Cl in the luminal contents of upper, middle, and lower small intestine and colon of infected mice were determined by flame photometry (Na+, K+) and an ion selective microelectrode (Cl). In M-SI, maximal disturbance of water transport occurred at 72 h postinfection (PI): Infected tissue exhibited net water secretion. Water transport was also impaired at 144 h PI. Net secretion of Cl occurred at 72 h PI, with some evidence of a second phase of reduced magnitude at 120-144 h PI. The magnitude and statistical significance of changes in Na+ transport were both less than those for Cl, but the pattern of change was similar to that for Cl. Luminal concentrations of Na+ were elevated between 48 and 144 h PI in the small intestine; this was particularly so in distal regions. Luminal Cl concentration was maximally elevated to a considerable degree at 72 h PI and remained high at 96 h PI throughout the small intestine; thereafter, Cl concentration returned to near normal. K+ concentration was unchanged in the small intestinal lumen; in the colon, however, K+ concentrations were depressed 72-168 h PI. In the light of previous data from this laboratory, the present data are interpreted as evidence for a secretory component in rotavirus-induced diarrhea. © 1990 Raven Press Ltd, New York.