How Does Inhaled Nitric Oxide Reach Peripheral Tissues?

Abstract

Conventional wisdom would dictate that nitric oxide is a local autocoid with spatially limited effects. Over the last few years, we, and others have challenged this view and have used inhaled nitric oxide to demonstrate that despite its administration in lung, it can impact the peripheral vasculature. This chapter summarizes some of the evidence to support the contention that nitric oxide can impact peripheral vasculatures presumably via a stabilizing moiety in the circulation. One possibility is the formation of S-Nitrosothiols, which extend the half-life of nitric oxide many-fold. In this chapter I provide evidence that S-nitrosothiols exist in the vasculature, particularly during nitric oxide inhalation. Finally, I highlight the limited evidence for the role that these potent vasodilating molecules may play as physiologically and therapeutically important regulators of the vascular system.