L-NIL is a potent inhibitor of nitric oxide synthase (NOS) that permeates the cell membrane. NOS is expressed in the liver and can be stimulated with a combination of lipopolysaccharides and cytokines. Nitric oxide (NO) is produced by NOS and plays an important role in the cytotoxicity of macrophages, in the vascular system, and during neurotransmission. Research shows that L-NIL is 28-fold more selective at inhibiting miNOS in rats than the rat brain constitutive.
