TY - JOUR
T1 - Role of protein kinase C in calcium sensitization during muscarinic stimulation in airway smooth muscle
AU - Bremerich, Dorothee H.
AU - Warner, David O.
AU - Lorenz, Robert R.
AU - Shumway, Robin
AU - Jones, Keith A.
PY - 1997
Y1 - 1997
N2 - Muscarinie receptor stimulation increases Ca2+ sensitivity, i.e., the amount of force produced at a constant submaximal cytosolic Ca2+ concentration ([Ca2+](i)), in permeabilized smooth muscle preparations. It is controversial whether this increase in Ca2+ sensitivity is in part mediated by protein kinase C (PKC). With the use of a β-escin permeabilized canine tracheal smooth muscle (CTSM) preparation, the effect of four putative PKC inhibitors [calphostin C, chelerythrine chloride, a pseudosubstrate inhibitor for PKC [PKC peptide-(19-31)], and staurosporine) on Ca2+ sensitization induced by acetylcholine (ACh) plus GTP was determined. Proincubation with each of the inhibitors did not effect subsequent Ca2+ sensitization induced by muscarinic receptor stimulation in the presence of a constant submaximal [Ca2+](i), neither did any of these compounds reverse the increase in Ca2+ sensitivity induced by ACh plus GTP. Administration of a 1,2-diacylglycerol analog, 1-oleoyl-2-acetyl-sn-glycerol, did not induce Ca2+ sensitization at a constant submaximal [Ca2+](i). Thus we found no evidence that PKC mediates increases in Ca2+ sensitivity produced by muscarinic receptor stimulation in permeabilized CTSM.
AB - Muscarinie receptor stimulation increases Ca2+ sensitivity, i.e., the amount of force produced at a constant submaximal cytosolic Ca2+ concentration ([Ca2+](i)), in permeabilized smooth muscle preparations. It is controversial whether this increase in Ca2+ sensitivity is in part mediated by protein kinase C (PKC). With the use of a β-escin permeabilized canine tracheal smooth muscle (CTSM) preparation, the effect of four putative PKC inhibitors [calphostin C, chelerythrine chloride, a pseudosubstrate inhibitor for PKC [PKC peptide-(19-31)], and staurosporine) on Ca2+ sensitization induced by acetylcholine (ACh) plus GTP was determined. Proincubation with each of the inhibitors did not effect subsequent Ca2+ sensitization induced by muscarinic receptor stimulation in the presence of a constant submaximal [Ca2+](i), neither did any of these compounds reverse the increase in Ca2+ sensitivity induced by ACh plus GTP. Administration of a 1,2-diacylglycerol analog, 1-oleoyl-2-acetyl-sn-glycerol, did not induce Ca2+ sensitization at a constant submaximal [Ca2+](i). Thus we found no evidence that PKC mediates increases in Ca2+ sensitivity produced by muscarinic receptor stimulation in permeabilized CTSM.
KW - Activator
KW - Calcium sensitivity
KW - Canine
KW - Lung
KW - Protein kinase C inhibitors
KW - Second messenger systems
KW - Trachea
KW - β-escin
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U2 - 10.1152/ajplung.1997.273.4.l775
DO - 10.1152/ajplung.1997.273.4.l775
M3 - Article
C2 - 9357852
AN - SCOPUS:0030725480
SN - 1040-0605
VL - 273
SP - L775-L781
JO - American Journal of Physiology - Lung Cellular and Molecular Physiology
JF - American Journal of Physiology - Lung Cellular and Molecular Physiology
IS - 4 17-4
ER -