HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 294/2/G467    most recent 00415.2007v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (1) Citing Articles via Google Scholar Google Scholar Articles by Balemba, O. B. Articles by Mawe, G. M. Search for Related Content PubMed PubMed Citation Articles by Balemba, O. B. 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

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

This article has been cited by other articles:

				A. C. Bartoo, M. T. Nelson, and G. M. Mawe ATP induces guinea pig gallbladder smooth muscle excitability via the P2Y4 receptor and COX-1 activity Am J Physiol Gastrointest Liver Physiol, June 1, 2008; 294(6): G1362 - G1368. [Abstract] [Full Text] [PDF]