Prostanoids inhibit intestinal NaCl absorption in experimental porcine cryptosporidiosis

Recent studies of piglet cryptosporidiosis have shown that impaired Na(+)-coupled glucose absorption is associated with a loss of two thirds of the villous absorptive surface and an inflammatory infiltration of the lamina propria. Because inflammatory cells release eicosanoids that may alter electrolyte transport, the present study examined the role of prostanoids on NaCl transport.

Ileal mucosa was stripped of its muscle layers and mounted in Ussing chambers in the presence or absence of indomethacin. Adjacent tissue was also frozen for subsequent extraction and radioimmunoassay of prostaglandin E2 (PGE2).

Results showed that net Na+ absorption is inhibited and net Cl- secretion is induced in infected piglets. Indomethacin restored net Na+ and Cl- absorption to control levels and exogenous PGE reversed this effect. Radioimmunoassay of tissue extracts showed that PGE2 increased from 56.7 +/- 9.6 ng/cm2 in control to 134 +/- 16.8 ng/cm2 in infected ileum (P < 0.01).

These data indicate that in addition to the Na-glucose malabsorption arising from structural damage, part of the diarrhea of these infected animals must be attributed to local prostanoid production.