Neural integration of jejunal motility and ion transport in nematode-infected ferrets

Abstract

Jejunal motility measured manometrically and coupled fluctuations in electrogenic ion transport measured as transmural potential differences (PD) were simultaneously studied in ferrets infected with enteric stages of the parasitic nematode, Trichinella spiralis. Vagotomy in uninfected ferrets abolished jejunal motility clusters and associated PD oscillations. Conversely, in infected ferrets on days 8-12 postinfection (PI), vagotomy did not abolish jejunal motility and PD. Calculated motility indexes (MI) indicated that postvagotomy MI decreased to 12% of prevagotomy MI in uninfected ferrets, whereas, in T.spiralis-infected ferrets, postvagotomy MI declined only to 48% of prevagotomy MI. Atropine abolished all vagotomy-resistant residual jejunal motility clusters and PD oscillations in T. spiralis-infected ferrets. Decreased intestinal content of substance P (27% of control) and vasoactive intestinal peptide (41% of control) and increased myeloperoxidase activity (262% of control) were detected in T. spiralis-infected ferrets. Our results suggest that integrated neural control of muscular and epithelial effectors in the small bowel is altered by nematode-induced inflammation.