Enhanced arterial contractile responses in diabetic hypercholesterolemic pig carotid arteries.
BACKGROUND
Two of the common risk factors for atherosclerosis are diabetes and hypercholesterolemia.


OBJECTIVE
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.
Bagwell
C A
CA
Department of Surgery, Institute for Molecular Medicine and Genetics, Medical College of Georgia, Augusta 30912-3175, USA.
Brophy
C
C
D000818:Animals; D002339:Carotid Arteries / Q000502:physiology*; D003921:Diabetes Mellitus, Experimental / Q000503:physiopathology*; D006937:Hypercholesterolemia / Q000503:physiopathology*; D066298:In Vitro Techniques; D011493:Protein Kinase C / Q000502:physiology; D012701:Serotonin / Q000494:pharmacology; D013311:Streptozocin; D013552:Swine; D014661:Vasoconstriction / Q000187:drug effects*
D012701:Serotonin; D013311:Streptozocin; D011493:Protein Kinase C