Endothelial nitric-oxide synthase (eNOS), also known as NOS3, it is an important enzyme in the cardiovascular system. It is a reactive free radical which acts as a biologic mediator in several processes, including neurotransmission and antimicrobial and antitumoral activities. Nitric oxide is synthesized from L-arginine by nitric oxide synthases. Variations in this gene are associated with susceptibility to coronary spasm.
