Faculty Collaboration Database

Intestinal myoelectric alterations in rats chronically infected with the tapeworm Hymenolepis diminuta. Am J Physiol 1994 Nov;267(5 Pt 1):G851-8

Date

11/01/1994

Pubmed ID

7977747

DOI

10.1152/ajpgi.1994.267.5.G851

Scopus ID

2-s2.0-0028116998 (requires institutional sign-in at Scopus site)   30 Citations

Abstract

This study determined that intestinal myoelectric activity was profoundly altered during a strictly luminal, chronic, tapeworm infection. Chronically implanted bipolar electrodes were attached to five sites on the serosal surface of the rat small intestine. One was placed on the duodenum, three on the jejunum, and the fifth on the ileum. Electromyographic recording in nonfasted unanesthetized animals was begun at day 5 postsurgery. All electromyographic recordings were analyzed for slow wave (SW) frequency, phase III frequency, duration of phase III, and percentage of SW with spike potentials. Three initial control recordings prior to infection confirmed the presence of normal interdigestive motility characterized by the three phases (I, II, III) of the migrating myoelectric complex (MMC). Two nonpropulsive myoelectric alterations were observed in infected animals: the repetitive bursts of action potentials (RBAP) and periods of sustained spike potentials (SSP). Myoelectric activity from infected animals indicated decreased cycling of the interdigestive MMC. RBAP and SSP were more prevalent in the distal small intestine corresponding to tapeworm location. The percent of spike potential activity indicated that there was a reversal in the spike potential gradient on the small intestine. The number of spike potentials was maximal in caudal and minimal in oral intestine. We propose that overall localized increases in myoelectric spike potential activity represent increased contractility and decreased propulsion triggered by the presence of the tapeworm. These motility changes were surprising, since the tapeworm Hymenolepis diminuta does not penetrate the intestinal mucosa. This interaction between parasite and host may prevent expulsion of the tapeworm from the small intestine.

Author List

Dwinell MB, Bass P, Oaks JA

Author

Michael B. Dwinell PhD Director, Professor in the Microbiology and Immunology department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Action Potentials
Animals
Chronic Disease
Electromyography
Gastrointestinal Motility
Hymenolepiasis
Intestines
Male
Myoelectric Complex, Migrating
Rats
Rats, Sprague-Dawley