Altered jejunal potassium (Rb+) transport in piglet rotavirus enteritis.
To determine the mechanisms of K+ loss in viral diarrhea, K+ fluxes (estimated by tracer Rb+ flows) across piglet jejunum in Ussing chambers were determined. Normal jejunum was characterized by an indomethacin-sensitive short-circuit current and a small K+ secretory flow. Rotavirus-infected gut secreted K+ at high rates, probably resulting from increased prostaglandin generation because secretion was abolished by indomethacin. Tissues pretreated with indomethacin responded to 8-bromoadenosine 3',5'-cyclic monophosphate acid and 16,16-dimethyl-prostaglandin E2 with K+ secretion. The secretory response in rotavirus-infected jejunum was no greater than that in normal tissue. Serosal addition of Ca2+ ionophore A23187 caused K+ secretion in normal but not rotavirus-infected jejunum. To inhibit the basolateral uptake of K+ and reduce the driving force for secretion, ouabain was added to the bath. Ouabain unmasked a K+ absorptive process in normal intestine, which was not seen in rotavirus-infected tissue. K+ absorption was inhibited by 3-(cyanomethyl)-2-methyl-8-(phenyl-methoxy)imidazo (1,2 alpha)pyridine (Sch-28080) and omeprazole. We speculate that the high fecal K+ losses observed in human rotavirus enteritis might be caused by an imbalance between K+ secretion and an impaired apical K+ absorptive mechanism in the crypt-type epithelium.
Woodard
J P
JP
School of Medicine, Department of Pediatrics, University of North Carolina at Chapel Hill.
Chen
W
W
Keku
E O
EO
Liu
S C
SC
Lecce
J G
JG
Rhoads
J M
JM
D000208:Acute Disease; D000818:Animals; D000831:Animals, Newborn; D001692:Biological Transport; D004751:Enteritis / Q000378:metabolism* / Q000382:microbiology*; D007213:Indomethacin / Q000494:pharmacology; D007583:Jejunum / Q000378:metabolism*; D010042:Ouabain / Q000494:pharmacology; D011188:Potassium / Q000378:metabolism*; D012016:Reference Values; D012400:Rotavirus Infections; D012413:Rubidium / Q000378:metabolism; D013552:Swine
D010042:Ouabain; D012413:Rubidium; D011188:Potassium; D007213:Indomethacin