l-Arginine for the prevention and treatment of coronary artery disease

Role of endothelial dysfunction in atherosclerosis

As the major regulator of vascular homeostasis, the endothelium exerts a number of vasoprotective effects, such as vasodilation, suppression of smooth muscle cell growth, and inhibition of inflammatory responses. Many of these effects are largely mediated by nitric oxide, the most potent endogenous vasodilator. Nitric oxide opposes the effects of endothelium-derived vasoconstrictors and inhibits oxidation of low-density lipoprotein. A defect in the production or activity of nitric oxide leads to endothelial dysfunction, signaled by impaired endothelium-dependent vasodilation. Accumulating evidence suggests that endothelial dysfunction is an early marker for atherosclerosis and can be detected before structural changes to the vessel wall are apparent on angiography or ultrasound. Many of the risk factors that predispose to atherosclerosis can also cause endothelial dysfunction, and the presence of multiple risk factors has been found to predict endothelial dysfunction. A number of clinical trials have shown that 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) improve endothelial dysfunction in patients with coronary risk factors beyond what could be attributed to their impact on plasma lipids. Studies have elucidated several possible mechanisms by which statin therapy may improve endothelial dysfunction, including upregulation of nitric oxide production or activity and reduction of oxidative stress.

Mechanisms underlying the programming of small artery dysfunction: review of the model using low protein diet in pregnancy in the rat

Human and animal studies have shown that unbalanced maternal nutrition is associated with the development of cardiovascular and metabolic disease in adulthood. In the Southampton maternal low protein model (SMLP), protein deprivation (50%) throughout pregnancy in rats leads to elevated blood pressure in adult offspring. Impaired peripheral arterial function may contribute to the cardiovascular dysfunction observed in these offspring. This review discusses the impact of such a dietary insult on the vascular function of resistance arteries from pregnant rats (pF(o)), their offspring (F(1)), the pregnant offspring (pF(1)) and the second generation (F(2)). At each stage, disturbances in endothelium-dependent relaxation were observed, implicating changes in endothelial nitric oxide (NO)-guanylate cyclase (GC) signalling pathway in the vascular adaptations to pregnancy and the programmed effects on offspring.