View : 61 Download: 0

Effects of myosin light chain kinase inhibitors on caubachol-activated nonselective cationic current in guinea-pig gastric myocytes

Title
Effects of myosin light chain kinase inhibitors on caubachol-activated nonselective cationic current in guinea-pig gastric myocytes
Authors
Kim Y.C.Kim S.J.Kang T.M.Suh S.H.So I.Kim K.W.
Ewha Authors
서석효
SCOPUS Author ID
서석효scopus
Issue Date
1997
Journal Title
Pflugers Archiv European Journal of Physiology
ISSN
0031-6768JCR Link
Citation
vol. 434, no. 4, pp. 346 - 353
Indexed
SCI; SCIE; SCOPUS scopus
Abstract
The effects of myosin light chain kinase inhibitors on muscarinic stimulation-activated nonselective cationic current (I(CCh)) in guinea-pig gastric antral myocytes were studied using the whole-cell patch-clamp technique. I(CCh) was induced by carbachol (CCh, 50 μM) at a holding potential of -30 mV or -60 mV. ML-7, a chemical inhibitor of myosin light chain kinase (MLCK), inhibited I(CCh) concentration dependently in a reversible manner (53 ± 8.6% at 1 μM, mean ± SE, n = 11). In addition, amplitudes of I(CCh) were only 37 ± 2.7% of the daily control values following the addition of a peptide inhibitor of MLCK to the pipette solution. On the other hand, ML-7 had an inhibitory effect on voltage-operated Ca 2+ channel current. The peak value of Ba 2+ current at 0 mV was reduced to 35 ± 7.4% (n = 9) by 3 μM of ML-7. As I(CCh) is known to have an intracellular Ca 2+ dependence, we tried to exclude the possibility that ML-7 inhibited I(CCh) indirectly via suppression of Ca 2+ current and the similar inhibitory effects of ML7 on I(CCh) were confirmed under the following conditions: (1) clamp of membrane potential at -60 mV; (2) clamp of intracellular [Ca 2+] to 1 μM by 10 mM BAPTA; (3) pre-inhibition of Ca 2+ channel by verapamil. Different from the effects on I(CCh), ML-7 barely inhibited the same cationic current induced by guanosine 5'-O-(3-thiotriphosphate) (GTP[γS], 0.2 mM) in the pipette solution. These results suggest that a Ca 2+-calmodulin-MLCK-dependent pathway can modulate the activation of I(CCh) in guinea-pig gastric antral myocytes.
DOI
10.1007/s004240050407
Appears in Collections:
의과대학 > 의학과 > Journal papers
Files in This Item:
There are no files associated with this item.
Export
RIS (EndNote)
XLS (Excel)
XML


qrcode

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

BROWSE