Action of Iron Nitrosyl Complexes,NO Donors,on the Activity of Sarcoplasmic Reticulum Ca2+-ATPase and Cyclic Guanosine Monophosphate Phosphodiesterase

The effect of iron nitrosyl complexes, NO donors, of a general formula [Fe₂(L)₂(NO)₄] with functional sulfur-containing ligands (L-3-nitro-phenol-2-yl, 4-nitro-phenol-2-yl, or 1-methyl-tetrazol-5-yl) on the activity of sarcoplasmic reticulum Ca²⁺-ATPase and cyclic guanosine monophosphate phosphodiesterase (cGMP PDE) was studied. The test complexes uncoupled the hydrolytic and transport functions of Ca²⁺- ATPase, thus disturbing the balance of Ca²⁺ ions in cells, which may affect the formation of thrombi and adhesion of metastatic cells to the endothelium of capillaries. They also inhibited the activity of cGMP PDE, thereby contributing to the accumulation of the second messenger cGMP. The studied iron nitrosyl complexes can be considered as potential drugs.