. 1993; 6(2): 88-94 | |||
The Effects of Aspirin Metabolites on Nadh-Methaemoglobin Reductase (Diaphorase) Activity in Human ErythrocytesM. M. Ziu, A. S. M. GiasuddinFrom Department of Laboratory Medicine, Al-Arab Medical University, Benghazi-LIBYA.The present study was undertaken to know whether aspirin metabolites (sodium salicylate, Na-SA; sodium gentisate, Na-GA; sodium salicylate, Na-SA; sodium gentisate, Na-GA; sodium salicylurate, Na-SU) exert their reported toxic effects by inhibiting the enzyme 'NADH-Methaemoglobin (MHb) reductase (Diaphorase)' in normal adult human erythrocytes. The inhibition of the enzyme activity in normal haemolysates was observed to be highest with Na-SU, followed by Na-GA and Na-SA respectively (92%, 90% and 75% inhibition with 0.13 mM Na-SU, 50 mM Na-GA and 50 mM Na-SA respectively). The Linewearer-Burk plots from the kinetic studies (Vmax) with varying concentrations of the substrate 'NADH' indicated that the inhibition of the enzyme activity by all the three aspirin metabolites were of non-competitive type [Vmax(U)NADH alone: 47.64 ± 4.56, NADH + 10 mM Na-SA: 24.39 ± 2.34, P<0.02; Vmax (U)NADHNADH alone: 16.67 ± 1.12, M. M. Ziu, A. S. M. Giasuddin. The Effects of Aspirin Metabolites on Nadh-Methaemoglobin Reductase (Diaphorase) Activity in Human Erythrocytes. . 1993; 6(2): 88-94 Sorumlu Yazar: M. M. Ziu, Libya |
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