AJP - GI AJP: Advances in Physiology Education
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Am J Physiol Gastrointest Liver Physiol 294: G467-G476, 2008. First published November 29, 2007; doi:10.1152/ajpgi.00415.2007
0193-1857/08 $8.00
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
294/2/G467    most recent
00415.2007v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Google Scholar
Right arrow Articles by Balemba, O. B.
Right arrow Articles by Mawe, G. M.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Balemba, O. B.
Right arrow Articles by Mawe, G. M.

NEUROREGULATION AND MOTILITY

Role of mitochondria in spontaneous rhythmic activity and intracellular calcium waves in the guinea pig gallbladder smooth muscle

Onesmo B. Balemba,1,* Aaron C. Bartoo,1,* Mark T. Nelson,2 and Gary M. Mawe1,2

Departments of 1Anatomy and Neurobiology and 2Pharmacology, University of Vermont College of Medicine, Burlington, Vermont

Submitted 14 September 2007 ; accepted in final form 27 November 2007

Mitochondrial Ca2+ handling has been implicated in spontaneous rhythmic activity in smooth muscle and interstitial cells of Cajal. In this investigation we evaluated the effect of mitochondrial inhibitors on spontaneous action potentials (APs), Ca2+ flashes, and Ca2+ waves in gallbladder smooth muscle (GBSM). Disruption of the mitochondrial membrane potential with carbonyl cyanide 3-chlorophenylhydrazone, carbonyl cyanide 4-(trifluoromethoxy) phenylhydrazone, rotenone, and antimycin A significantly reduced or eliminated APs, Ca2+ flashes, and Ca2+ waves in GBSM. Blockade of ATP production with oligomycin did not alter APs or Ca2+ flashes but significantly reduced Ca2+ wave frequency. Inhibition of mitochondrial Ca2+ uptake and Ca2+ release with Ru360 and CGP-37157, respectively, reduced the frequency of Ca2+ flashes and Ca2+ waves in GBSM. Similar to oligomycin, cyclosporin A did not alter AP and Ca2+ flash frequency but significantly reduced Ca2+ wave activity. These data suggest that mitochondrial Ca2+ handling is necessary for the generation of spontaneous electrical activity and may therefore play an important role in gallbladder tone and motility.

motility; sarcoplasmic reticulum; calcium transients; slow waves; action potentials


Address for reprint requests and other correspondence: G. M. Mawe, Dept. of Anatomy and Neurobiology, Univ. of Vermont College of Medicine, 89 Beaumont Ave., D406 Given Bldg., Burlington, VT 05405 (e-mail: gary.mawe{at}uvm.edu)






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online
Copyright © 2008 by the American Physiological Society.