Phenotype Changes of the Vascular Smooth Muscle Cell Regulate P2 Receptor Expression as Measured by Quantitative RT-PCR

doi:10.1006/bbrc.1998.9083

Biochemical and Biophysical Research Communications

Volume 248, Issue 3, 30 July 1998, Pages 864-870

https://doi.org/10.1006/bbrc.1998.9083 Get rights and content

Abstract

Studies using selective agonists have suggested that the contractile effect of extracellular nucleotides, such as ATP and UTP, in blood vessels is mediated mainly by P2X₁receptors with a smaller contribution of P2Y receptors while the mitogenic effect is mediated by P2Y (P2Y₁, P2Y₂, P2Y₄, and P2Y₆) receptors with no effect of P2X₁receptors. This indicates a difference in P2 receptor expression between the contractile and the synthetic phenotype of the SMC. To measure the expression of mRNA for these receptors a competitive RT-PCR assay was developed that utilised synthetic RNA-competitors allowing determination of the number of mRNA copies for each receptor in the samples. In the synthetic phenotype the mitogenic P2Y₁and P2Y₂receptor transcripts were upregulated by 342- and 8-fold, respectively, while the contractile P2X₁receptor is totally downregulated and the P2Y₄and P2Y₆receptors were unchanged. This plasticity of the receptor expression may be important in the transition from the contractile to the synthetic SMC phenotype.

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^☆: Turner, J. T.Weisman, G. A.Fedan, J. S.

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Regular ArticlePhenotype Changes of the Vascular Smooth Muscle Cell Regulate P2 Receptor Expression as Measured by Quantitative RT-PCR☆

Abstract

Circulation

General Pharmacol.

Current Opinion Neurobiology

Int. Rev. Cytology

Eur. J. Pharmacol. Mol. Pharmacol. Sect.

Am. J. Physiol.

FEBS Lett.

Proc. Natl. Acad. Sci. USA

Am. J. Physiol.

Nature

Biochem. Biophys. Res. Commun.

Endocrinology

J. Biol. Chem.

J. Neurochem.

Microbeam Anal. Soc. J.

J. Clin. Microbiol.

Regular Article
Phenotype Changes of the Vascular Smooth Muscle Cell Regulate P2 Receptor Expression as Measured by Quantitative RT-PCR☆