R O Wright1, B Magnani, M W Shannon, A D Woolf. 1. Division of General Pediatrics, Children's Hospital, Boston, Massachusetts, USA. wright_r@a1.tch.harvard.edu
Abstract
STUDY OBJECTIVE: To determine whether N-acetylcysteine (NAC reduces methemoglobin. METHODS: We carried out an in vitro laboratory experiment in which five healthy adult volunteers donated blood. Each sample was divided equally among three test tubes. Tube 1 served as a negative control. Sodium nitrite .18 mol/L with dextrose .23 mol/L was added to tube 2 and to tube 3. Next, phosphate-buffered saline solution (PBS) was added to tube 2 and NAC (200 mg/mL) to tube 3. Serial methemoglobin levels were measured over 5.5 hours. RESULTS: Maximum methemoglobin levels were observed at 1.5 hours for both the NAC-nitrite and the PBS-nitrite sample (62.7% +/- 8.1% and 65.1% +/- 7.0%, respectively; data expressed as mean +/- SD). The mean difference in methemoglobin between NAC-nitrite and PBS-nitrite was significant at 4.5 hours (29.3% +/- 23.0%, P = .046). The mean rate of methemoglobin decline in NAC-nitrite samples was also different from that of PBS-nitrite samples (10.7% +/- 1.0% versus 2.9% +/- 2.3%, P = .002). The rate of decline was linea (zero order) in the NAC nitrite samples and represented by the equation: % change methemoglobin = .18 x time in minutes. Area under the concentration-time curve was also different among groups (P < .05). CONCLUSION: In this in vitro model, NAC reduced chemically induced methemoglobin.
STUDY OBJECTIVE: To determine whether N-acetylcysteine (NAC reduces methemoglobin. METHODS: We carried out an in vitro laboratory experiment in which five healthy adult volunteers donated blood. Each sample was divided equally among three test tubes. Tube 1 served as a negative control. Sodium nitrite .18 mol/L with dextrose .23 mol/L was added to tube 2 and to tube 3. Next, phosphate-buffered saline solution (PBS) was added to tube 2 and NAC (200 mg/mL) to tube 3. Serial methemoglobin levels were measured over 5.5 hours. RESULTS: Maximum methemoglobin levels were observed at 1.5 hours for both the NAC-nitrite and the PBS-nitrite sample (62.7% +/- 8.1% and 65.1% +/- 7.0%, respectively; data expressed as mean +/- SD). The mean difference in methemoglobin between NAC-nitrite and PBS-nitrite was significant at 4.5 hours (29.3% +/- 23.0%, P = .046). The mean rate of methemoglobin decline in NAC-nitrite samples was also different from that of PBS-nitrite samples (10.7% +/- 1.0% versus 2.9% +/- 2.3%, P = .002). The rate of decline was linea (zero order) in the NAC nitrite samples and represented by the equation: % change methemoglobin = .18 x time in minutes. Area under the concentration-time curve was also different among groups (P < .05). CONCLUSION: In this in vitro model, NAC reduced chemically induced methemoglobin.
Authors: Darren M Roberts; Renate Heilmair; Nick A Buckley; Andrew H Dawson; Mohamed Fahim; Michael Eddleston; Peter Eyer Journal: BMC Clin Pharmacol Date: 2009-02-16
Authors: Andrew J Jezewski; Yu-Hsi Lin; Julie A Reisz; Rachel Culp-Hill; Yasaman Barekatain; Victoria C Yan; Angelo D'Alessandro; Florian L Muller; Audrey R Odom John Journal: Front Cell Infect Microbiol Date: 2021-09-16 Impact factor: 6.073