7V-acetylcysteine

Principle Creatine kinase is activated by 7V-acetylcysteine within 80 s. 

During an incubation and measurement phase of altogether 240 seconds, the reflectance values of the formed dye are measured at 340 nm every 5 seconds between the 160th and 240th second. 7V-acetylcysteine was added to activate the oxidized creatine kinase (CK). Myokinase inhibitors prevent interference with the assay by this enzyme. From the measured reflectance values the instrument calculates the CK activity of the sample via a calibration curve produced with two different calibrators (high/low). 

Sagara M, Satoh J, Wada R, Yagihashi S, Takahashi K, Fukuzawa M, et al. Inhibition of development of peripheral neuropathy in streptozotocin-induced diabetic rats with 7V-acetylcysteine. Diabetologia 1996 39 263-269. 

Weber, G. L., Steenwyk, R. C., Nelson, S. D., Pearson, P. G. Identification of 7V-acetylcysteine conjugates of l,2-dibromo-3-chloropropane evidence for cytochrome P450 and glutathione mediated bioactivation pathways. Chem. Res. Toxicol. 1995,8, 560-573. 

Some practitioners advocate the use of oral 7V-acetylcysteine, although the evidence is conflicting. In a randomized placebo-controlled study of 200 patients who were given iodixanol, oral Al-acetylcysteine 600 mg bd the day before and on the day of the procedure or placebo were combined with intravenous saline 1 ml/kg/hour 12-24 hours before the procedure and 12-24 hours after [14 ]. The rates of contrast-induced nephrotoxicity were 8.1% in those who were given acetylcysteine and 5.9% in those who were given saline, a non-significant difference. The authors concluded that acetylcysteine did not prevent contrast-induced nephrotoxicity in patients who received iso-osmolar contrast media with adequate hydration. 

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