Microcirculatory dysfunction induced by cigarette smoking.

This review deals with the deleterious effects of cigarette smroking on the microcirculation, both in terms of morphological (i.e., vessel wall injury, capillary loss) and functional aspects. The latter concerns predominantly changes in tissue perfusion and its regullatory mechanisms (i.e., reactive hyperemia, sequestration of blood cells in the microcirculation). The mechanisms of action of cigarette smoking on the microcirculation include compromised endothelial-dependent voasorelaxation, platelet aggregation, emdothelial cell dysfunction and the activation of circulating leukocytes. Through these mechanisms, cigarette smoking elicits the aggregation and adhesion of leukocytes and/or platelets to the microvascular endothelium in venules and arterioles, as assessed by intravital fluorescence microscopy in the hamster skinfold chamber model. This model has allowed us to learn more about the participation of reactive oxygen species, inflammatory mediators, and adhesion molecules in the orchestration of microcirculatory dysfunction after cigarette smoking. In the final part of this review, the clinical consequences of microcirculatory dysfunction are discussed and an outlook is offered on potential prophylactic interventions (i.e., antioxidant vitamins) aimed at abrogating the deleterious action of cigarette smoking on the microcirculation.