Calcium sequestration by subcellular fractions isolated from vascular smooth muscle: Effect of cyclic nucleotides and prostaglandins

R. Clinton Webb, Ramesh C. Bhalla

Research output: Contribution to journalArticle

28 Scopus citations

Abstract

Microsomal vesicles and mitochondria derived from aortae of rat accumulate calcium in the presence of adenosine triphosphate and magnesium. The rate and extent of energy-linked calcium sequestration by microsomal vesicles were found to exhibit hydrogen ion and temperature dependency and nucleoside phosphate specificity. Calcium uptake (in the presence of oxalate) showed preference for nucleosides in the order ATP>ADP>GTP>UTP>ITP. Calcium accumulation by the subcellular fractions was also found to be dependent upon the concentration of calcium in the incubation medium. Cyclic AMP stimulated microsomal calcium binding while prostaglandins F and E2 had no specific effect. These agents did not alter the calcium sequestering mechanisms of the mitochondria. These data suggest that the vesicular and mitochondrial fraction may constitute an important factor in the regulation of calcium availability to the contractile mechanism of vascular smooth muscle.

Original languageEnglish (US)
Pages (from-to)145-157
Number of pages13
JournalJournal of molecular and cellular cardiology
Volume8
Issue number2
DOIs
StatePublished - Feb 1976

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Keywords

  • ATPase
  • Calcium
  • Cyclic AMP
  • Microsomal vesicles
  • Mitochondria
  • Prostaglandins
  • Vascular smooth muscle

ASJC Scopus subject areas

  • Molecular Biology
  • Cardiology and Cardiovascular Medicine

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