Nitrates, arterial function, wave reflections and coronary heart disease.

This chapter traces the history of nitroglycerin from the initial nitration of glycerol to its widespread clinical use. The pharmacologic differences between nitroglycerin and nitric oxide are described, as well as their similar mechanisms of action. The vasoactivity of nitroglycerin requires a biochemical transformation, the nature of which remains incompletely understood. This poorly defined mechanism probably also relates to the phenomenon of nitroglycerin tolerance. By increasing the distensibility of muscular arteries, nitroglycerin slows pulse wave velocity, reduces wave reflections and alters the shape of the aortic pulse. This alteration reduces the systolic blood pressure and left ventricular after load and helps to explain the usefulness of nitroglycerin in angina pectoris, congestive heart failure and isolated systolic hypertension.