Possible Interaction: Cysteine and Nitroglycerin

“The addition of captopril or L-cysteine (1 x 10(-6) M) enhanced the activity of both nitroglycerin and nicorandil, whereas addition of enalaprilat did not.”

“Liberation of nitric oxide (NO) from GTN and SPM 3672 measured in vitro was rather low and was markedly potentiated by addition of cysteine only in the case of GTN.”

“Pronounced activation of a partially purified human soluble guanylate cyclase (sGC) by GTN was observed only after addition of cysteine , whereas a comparative activation by SPM 3672 occurred with and without addition of this thiol.”

“N-Acetylcysteine, L-cysteine , and D-cysteine accelerated NTG degradation in whole blood, while a similar concentration of glutathione had no effect.”

“Our results indicated that neighboring Cys and Tyr residues can facilitate each other's oxidation in the presence of NTG.”

“The observed increase in formazan production and HMPS activity and the reduction of cell proliferation due to RA were augmented by co-treatment with either glyceryl trinitrate , molsidomine, CAS 936 or tetranitromethane plus cysteine.”

“ Cysteine (1 mM) enhanced cyclic GMP formation induced by sodium nitroprusside and nitroglycerin.”

“Preincubation of platelets with cysteine did not or only slightly increase the ability of isosorbide-5'-mononitrate and isosorbide dinitrate to inhibit aggregation, but a clear increase was observed after preincubation with nitroglycerin.”

“ Cysteine appears to be particularly effective in potentiating guanylate cyclase activation by NTG.”

“… L-cysteine and NAC … relaxations to GTN (0.1 nM-10 microM) as the GTN relaxation EC50 decreased compared with that of the untreated RTCS (L-cysteine, 0.….12 microM and NAC, 0.08 +/- 0.03 microM versus control 0.25 +/- 0.08 microM, n = 5, p < 0.05).”

“Previous studies have shown the effect of nitroglycerin on coronary microvessels < 100 microns in diameter is markedly enhanced by L-cysteine.”