Nitroarginine (N'-Nitro-L-arginine) is a competitive inhibitor of nitric oxide synthase which causes the selective reduction of blood flow to tumor cells[1].

Methylene Blue trihydrate (Basic blue 9) is a compound consisting of dark green crystals or crystalline powder, having a bronze-like luster. Solutions in water or alcohol have a deep blue color. Methylene Blue trihydrate is used as a bacteriologic stain and as an indicator. It inhibits soluble guanylyl cyclase and has been used to treat cyanide poisoning and to lower levels of methemoglobin. It also inhibits tau filament formation (IC50: 1.9μM).

1. L-Arginine (L-Arg) exhibits anti-atherosclerotic effect. 2. L-Arginine and soy enriched diet are effective in prevention of osteoporosis associated with diabetes mellitus. 3. Exogenous L-Arginine could enhance neonate lymphocyte proliferation through an interleukin-2-independent pathway. 4. A combination of oral L-citrulline and L-Arginine effectively and rapidly augments NO-dependent responses at the acute stage.

L-NAME hydrochloride (L-NAME HCl), a cell-permeable NO synthase inhibitor, displays Ki values of 4.4 μM, 15 nM, and 39 nM, for iNOS (mouse) , nNOS (bovine) , and eNOS (human), respectively.

Aminoguanidine hydrochloride (Hydrazinecarboximidamide) is a diamine oxidase and NO synthase inhibitor, used in the treatment of diabetic nephropathy.