Role of protein kinase C in calcium sensitization during muscarinic stimulation in airway smooth muscle.

Academic Article

Abstract

  • Muscarinic 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. Preincubation with each of the inhibitors did not affect 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.
  • Authors

    Keywords

  • activator, calcium sensitivity, canine, lung, protein kinase C inhibitors, second messenger systems, trachea, β-escin
  • Digital Object Identifier (doi)

    Pubmed Id

  • 20645334
  • Author List

  • Bremerich DH; Warner DO; Lorenz RR; Shumway R; Jones KA
  • Start Page

  • L775
  • End Page

  • L781
  • Volume

  • 273
  • Issue

  • 4