Rho A/Rho kinase: human umbilical artery mRNA expression in normal and pre eclamptic pregnancies and functional role in isoprostane-induced vasoconstriction.

Journal Article

Pre eclampsia represents a state of increased or prolonged vasoconstriction, partially linked to the potent vasocontractile effect of isoprostanes. The process of Rho A-mediated calcium sensitisation is inherent to a state of prolonged contractility in many smooth muscle types. The aim of this study was (1) to investigate mRNA expression levels of Rho A and Rho kinase isoforms (I and II) in the umbilical artery from normotensive and pre eclamptic women and (2) to determine whether the effects of two isoprostanes, 8-iso prostaglandin F(2alpha) (8-iso PGF2alpha) and 8-iso prostaglandin E(2) (8-iso PGE(2)), on umbilical artery tone, were mediated via the Rho kinase pathway. Real-time RT-PCR using primers for Rho A, ROCK I and ROCK II was performed on total RNA isolated from umbilical artery specimens obtained from normotensive and pre eclamptic women. The effects of both isoprostanes (n = 6) (in the absence and presence of the specific Rho kinase inhibitor Y-27632), on umbilical artery tone were measured, and compared with control recordings. Rho A mRNA expression levels were significantly lower in umbilical artery samples obtained from pre eclamptic women (n = 4) in comparison to those from normotensive women (n = 6) (P < 0.05). ROCK I and ROCK II mRNA levels were similar in both vessel types (P > 0.05). Both isoprostanes exerted a significant concentration-dependent vasocontractile effect (n = 7) (P < 0.001) on umbilical artery. For 8-iso PGE(2), this effect was antagonised by Y-27632 (n = 6) (P < 0.01). The significant reduction of Rho A mRNA levels in umbilical arteries from pregnancies complicated by pre eclampsia may serve to counteract the diminished perfusion associated with the pathophysiology of pre eclampsia. The vasocontractile effect of 8-iso PGE(2) in pre eclampsia may in part be mediated via the Rho kinase pathway.

Full Text

Duke Authors

Cited Authors

  • Friel, AM; Sexton, DJ; O'reilly, MW; Smith, TJ; Morrison, JJ

Published Date

  • July 2006

Published In

Volume / Issue

  • 132 / 1

Start / End Page

  • 169 - 176

PubMed ID

  • 16816342

International Standard Serial Number (ISSN)

  • 1470-1626

Digital Object Identifier (DOI)

  • 10.1530/rep.1.01088

Language

  • eng

Conference Location

  • England