Effect of nitroso compounds on Na/K-ATPase

Abstract

Thiol containing NO.-derivatives were found to inhibit the activity of brain and kidney Na/K-ATPase. S-Nitrosogluthatione demonstrated only minor inhibiting activity, while dinitrosyl iron complexes (DNIC) with cysteine or glutathione were much more effective. Brain Na/K-ATPase is more vulnerable to inhibiting action than kidney Na/K-ATPase. Inhibition of the activity is accompanied by a decrease in amount of protein thiol groups and a change in the substrate dependence curve of the enzyme. Restoration of Na/K-ATPase activity by SH-reagent dithiothreitol or cysteine is accompanied by restoration of SH-groups of the enzyme. This suggests that blockade of SH-groups of Na/K-ATPase is responsible for the inhibition. The possibility that this blockade results in disordering of interprotomer interactions within the oligomeric complexes of Na/K-ATPase is suggested. Possible regulatory meaning of the effect of NO. derivatives is discussed.

Insights into the mechanism of erythrocyte Na+/K+‐ATPase inhibition by nitric oxide and peroxynitrite anion

“…25% inhibition) under the same conditions. A possible explanation for this discrepancy could be ascribed to the different isoforms present in porcine cerebral cortex (essentially α 2 + α 3 ) and rat erythrocyte (essentially α 1 ), even if Na + /K + -ATPase from brain has been reported to be more vulnerable to oxidative modification than that from kidney (Xie et al, 1995;Boldyrev et al, 1997).…”

Transformation of the {Fe(NO)2}9 Dinitrosyl Iron Complexes (DNICs) into S‐Nitrosothiols (RSNOs) Triggered by Acid–Base Pairs

“…15 N NMR spectra were recorded at 50.671 MHz, and 1024 transients were acquired with 2 s delay time. Chemical shifts (d) of 15 N NMR spectra are relative to neat 1 m NaNO 2 in D 2 O (d = 232 ppm) as the external standard. [31] Analyses of carbon, hydrogen, and nitrogen were obtained using a CHN analyzer (Heraeus).…”

“…(1-NAP) (yield 75 %) characterized by IR (ñ NO = 1808 (w), 1775 (s), 1751 cm À1 (s) (THF)), 15 N NMR, and UV/Vis spectroscopy, and singlecrystal X-ray diffraction. The single-crystal X-ray structure of 1-NAP is depicted in Figure S3 8 ]THF), which were assigned to anti (C 2h ) and syn configurations (C 2v ), respectively ( Figure S4 in the Supporting Information).…”

Nitric Oxide Synthase and Nitric Oxide Involvement in Different Toxicities

“…These metabolites, for example, can cause genotoxic effects by creating DNA damage [86]. In some other studies, N-nitroso compounds have been reported to alter the activity of creatine kinase, lactate dehydrogenase [87], pyruvate kinase [88], and Na/K-ATPase [89] enzymes.…”