Journal article
Whole cell current and membrane potential regulation by a human smooth muscle mechanosensitive calcium channel
American journal of physiology: Gastrointestinal and liver physiology, Vol.279(6), pp.G1155-G1161
12/01/2000
DOI: 10.1152/ajpgi.2000.279.6.G1155
PMID: 11093937
Abstract
Mechanotransduction is required for a wide variety of biological functions. The aim of this study was to determine the effect of activation of a mechanosensitive Ca2+ channel, present in human jejunal circular smooth muscle cells, on whole cell currents and on membrane potential. Currents were recorded using patch-clamp techniques, and perfusion of the bath (10 ml/min, 30 s) was used to mechanoactivate the L-type Ca2+ channel. Perfusion resulted in activation of L-type Ca2+ channels and an increase in outward current from 664 ± 57 to 773 ± 72 pA at +60 mV. Membrane potential hyperpolarized from −42 ± 4 to −50 ± 5 mV. In the presence of nifedipine (10 μM), there was no increase in outward current or change in membrane potential with perfusion. In the presence of charybdotoxin or iberiotoxin, perfusion of the bath did not increase outward current or change membrane potential. A model is proposed in which mechanoactivation of an L-type Ca2+ channel current in human jejunal circular smooth muscle cells results in increased Ca2+ entry and cell contraction. Ca2+ entry activates large-conductance Ca2+-activated K+channels, resulting in membrane hyperpolarization and relaxation.
Details
- Title: Subtitle
- Whole cell current and membrane potential regulation by a human smooth muscle mechanosensitive calcium channel
- Creators
- Adrian N Holm - Division of Gastroenterology and Hepatology, Departments of, Physiology and Biophysics andAdam Rich - Division of Gastroenterology and Hepatology, Departments of, Physiology and Biophysics andMichael G Sarr - Surgery, Mayo Clinic, Rochester, Minnesota 55905Gianrico Farrugia - Division of Gastroenterology and Hepatology, Departments of, Physiology and Biophysics and
- Resource Type
- Journal article
- Publication Details
- American journal of physiology: Gastrointestinal and liver physiology, Vol.279(6), pp.G1155-G1161
- DOI
- 10.1152/ajpgi.2000.279.6.G1155
- PMID
- 11093937
- ISSN
- 0193-1857
- eISSN
- 1522-1547
- Language
- English
- Date published
- 12/01/2000
- Academic Unit
- Gastroenterology and Hepatology; Internal Medicine
- Record Identifier
- 9984094485502771
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