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Retinal pericytes control expression of nitric oxide synthase and endothelin-1 in microvascular endothelial cells

Biomedical Sciences Research Institute Computer Science Research Institute Environmental Sciences Research Institute Nanotechnology & Advanced Materials Research Institute

Martin, AR, Bailie, JR, Robson, T, McKeown, Stephanie, Al-Assar, O, McFarland, A and Hirst, DG (2000) Retinal pericytes control expression of nitric oxide synthase and endothelin-1 in microvascular endothelial cells. MICROVASCULAR RESEARCH, 59 (1). pp. 131-139. [Journal article]

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Pericytes are known to communicate with endothelial cells by direct contact and by releasing cytokines such as TGF-beta. There is also strong evidence that pericytes act as regulators of endothelial cell proliferation and differentiation. We have investigated the effect of pericyte-conditioned medium (PCM) on proliferation of human microvascular endothelial cells in vitro, together with the expression of the vasoregulatory molecules, constitutive and inducible nitric oxide synthases (ecNOS and iNOS), and endothelin-1 (ET-1). Expression was measured at the mRNA level using semiquantitative RT-PCR for all three genes and at the protein level for ecNOS and iNOS using Western blotting. Growth curves for HMECs showed that PCM inhibits proliferation, eventually leading to cell death. Exposure to PCM repressed iNOS mRNA expression fivefold after 6 h. A similar, though delayed, reduction in protein levels was observed. ecNOS mRNA was slightly induced at 6 h, though there was no significant change in ecNOS protein. By contrast, ET-1 mRNA was induced 2.3-fold after 6 h exposure to PCM. We conclude that pericytes release a soluble factor or factors that are potent inhibitors of endothelial cell growth and promote vasoconstriction by up-regulating endothelin-1 and down-regulating iNOS. (C) 2000 Academic Press.

Item Type:Journal article
Faculties and Schools:Faculty of Life and Health Sciences
Faculty of Life and Health Sciences > School of Biomedical Sciences
Research Institutes and Groups:Biomedical Sciences Research Institute
Biomedical Sciences Research Institute > Pharmaceutical Science and Practice
ID Code:4338
Deposited By:Professor Stephanie McKeown
Deposited On:21 Dec 2009 12:13
Last Modified:01 Jun 2011 16:49

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