Antisense-inhibition of plasma membrane Ca2+ pump induces apoptosis in vascular smooth muscle cells

Jpn J Pharmacol. 2002 Oct;90(2):164-72. doi: 10.1254/jjp.90.164.

Abstract

The effect of antisense oligodeoxynucleotides (ODNs) of plasma membrane Ca(2+)-pumping ATPase (PMCA) on rat aortic vascular smooth muscle cells (VSMCs) in primary culture was examined. More than 80% of the PMCA expressed in cultured VSMCs was the PMCA-1B subtype. Exposed to antisense ODNs against PMCA-1, not only the expression of the PMCA protein but also mRNA of PMCA-1B was diminished in a concentration-dependent manner. Extracellular Na(+)-independent (45)Ca(2+) efflux catalyzed via PMCA was inhibited with antisense ODNs. Both the resting and ionomycin- or ATP-stimulated levels of intracellular Ca(2+) were increased by antisense ODNs. Furthermore, prolonged treatment with antisense ODNs caused apoptosis in VSMCs. The occurrence of apoptosis was inhibited by FK506, a potent immunosuppressant. These results demonstrate that the PMCA was specifically inhibited by antisense ODNs and suggest that PMCA plays an important role in regulation of intracellular Ca(2+) concentrations, especially at the resting condition to prevent an occurrence of apoptosis that may be induced through the activation of calcineurin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Aorta / cytology
  • Apoptosis / drug effects*
  • Apoptosis / physiology
  • Blotting, Western
  • Calcium / metabolism
  • Calcium-Transporting ATPases / antagonists & inhibitors*
  • Calcium-Transporting ATPases / biosynthesis
  • Calcium-Transporting ATPases / physiology*
  • Cell Membrane / metabolism
  • Cells, Cultured
  • Flow Cytometry
  • Male
  • Muscle, Smooth, Vascular / cytology
  • Muscle, Smooth, Vascular / enzymology
  • Muscle, Smooth, Vascular / metabolism*
  • Oligoribonucleotides, Antisense / pharmacology*
  • Phosphorylation
  • RNA, Messenger / biosynthesis
  • Rats
  • Reverse Transcriptase Polymerase Chain Reaction

Substances

  • Oligoribonucleotides, Antisense
  • RNA, Messenger
  • Calcium-Transporting ATPases
  • Calcium