C A Bagwell1, C Brophy. 1. Department of Surgery, Institute for Molecular Medicine and Genetics, Medical College of Georgia, Augusta 30912-3175, USA.
Abstract
BACKGROUND: Two of the common risk factors for atherosclerosis are diabetes and hypercholesterolemia. AIMS: The purpose of this investigation was to determine the independent and combined effects of experimental diabetes (DM) and hypercholesterolemia (HC) on vasomotor responses. METHODS: Yorkshire pigs were rendered hypercholesterolemic, diabetic, hypercholesterolemic/diabetic, or maintained as control. Dose dependent physiologic responses of the carotid artery smooth muscle to serotonin, sodium nitroprusside and phorbol ester were determined in a muscle bath. RESULTS: Vascular smooth muscle from the DM and HC/DM pigs showed enhanced contractile responses to serotonin. The HC pigs showed diminished contractile responses to serotonin. The DM smooth muscles had enhanced contractile responses to phorbol dibutyrate. There were no differences in endothelial-independent relaxation responses to sodium nitroprusside. CONCLUSIONS: This study demonstrates that diabetes enhances smooth muscle contractile responses in the presence and absence of hypercholesterolemia.
BACKGROUND: Two of the common risk factors for atherosclerosis are diabetes and hypercholesterolemia. AIMS: The purpose of this investigation was to determine the independent and combined effects of experimental diabetes (DM) and hypercholesterolemia (HC) on vasomotor responses. METHODS: Yorkshire pigs were rendered hypercholesterolemic, diabetic, hypercholesterolemic/diabetic, or maintained as control. Dose dependent physiologic responses of the carotid artery smooth muscle to serotonin, sodium nitroprusside and phorbol ester were determined in a muscle bath. RESULTS: Vascular smooth muscle from the DM and HC/DMpigs showed enhanced contractile responses to serotonin. The HC pigs showed diminished contractile responses to serotonin. The DM smooth muscles had enhanced contractile responses to phorbol dibutyrate. There were no differences in endothelial-independent relaxation responses to sodium nitroprusside. CONCLUSIONS: This study demonstrates that diabetes enhances smooth muscle contractile responses in the presence and absence of hypercholesterolemia.
Authors: Munir Boodhwani; Neel R Sodha; Shigetoshi Mieno; Shu-Hua Xu; Jun Feng; Basel Ramlawi; Richard T Clements; Frank W Sellke Journal: Circulation Date: 2007-09-11 Impact factor: 29.690