Vol. 283, Issue 2, G445-G456, August 2002
Interstitial cells of Cajal and electrical activity in
ganglionic and aganglionic colons of mice
Sean M.
Ward1,
Michael
D.
Gershon2,
Kathleen
Keef1,
Yulia R.
Bayguinov1,
Cheryl
Nelson1, and
Kenton M.
Sanders1
1 Department of Physiology and Cell Biology, School
of Medicine, University of Nevada, Reno, Nevada 89557; and
2 Department of Anatomy and Cell Biology, College of
Physicians and Surgeons, Columbia University, New York, New York 10032
An antibody directed against Kit protein was
used to investigate the distribution of interstitial cells of Cajal
(ICC) within the murine colon. The ICC density was greatest in the
proximal colon and decreased along its length. The distribution of the different classes of ICC in the aganglionic colons of lethal spotted (ls/ls) mice was found to be similar in age-matched
wild-type controls. There were marked differences in the electrical
activities of the colons from ls/ls mutants compared with
wild-type controls. In ls/ls aganglionic colons, the
circular muscle was electrically quiescent compared with the
spontaneous spiking electrical activity of wild-type tissues. In
ls/ls aganglionic colons, postjunctional neural responses
were greatly affected. Inhibitory junction potentials were absent or
excitatory junction potentials inhibited by atropine were observed. In
conclusion, the distribution of ICC in the ganglionic and aganglionic
regions of the colons from ls/ls mutants appeared similar to
that of wild-type controls. The electrical activity and neural
responses of the circular layer are significantly different in
aganglionic segments of ls/ls mutants.
Hirschsprung's disease; lethal spotted; enteric nerves; megacolon; gastrointestinal tract
