Nitric oxide and its antithrombotic action in the cardiovascular system.

Nitric oxide (NO) is a small gaseous molecule with an odd number of electrons and is rather soluble in hydrophobic phases. It was once known for its toxicity in the environment and for its applications in meat curing. After 1980 its importance was discovered in many physiological fields such as vascular regulation, neuronal communication, cytotoxic action by macrophages in bacterial infections etc. On the other side NO is involved in toxic shock, DNA damage and many pathological conditions. In 1992 the journal Science designated it as "molecule of the year" and in the last years there has been an explosion of publications on the subject. The publications are concerned with the spectroscopic characterisation of NO derivatives, with the reactivity of NO with Myoglobin, Cytochrome and Hemoglobin and in particular with the chemical activities and biological applications of nitric oxide donors and nitric oxide scavengers. All such researches have produced until now many patents. The most famous products are Viagra and nitroglycerine (Trinitrin). Particular attention is given to the applications of NO to cardiovascular and hematological disorders. To this aim the authors examine the physiologic activities of NO and the mechanism of its antiplatelet, vasodilatory and antiproliferative action. Studies in animals and humans are also reported. Another section examines the drugs that increase the endogenous production of NO and modulate its activities. The last part is dedicated to the novel antithrombotic agent Nitroaspirin. Methods for NO detection will also be examined.