Abstract
BackgroundInfusion of sodium nitrite could provide sustained therapeutic concentrations of nitric oxide (NO) for the treatment of a variety of vascular disorders. The study was developed to determine the safety and feasibility of prolonged sodium nitrite infusion.MethodologyHealthy volunteers, aged 21 to 60 years old, were candidates for the study performed at the National Institutes of Health (NIH; protocol 05-N-0075) between July 2007 and August 2008. All subjects provided written consent to participate.Twelve subjects (5 males, 7 females; mean age, 38.8±9.2 years (range, 21–56 years)) were intravenously infused with increasing doses of sodium nitrite for 48 hours (starting dose at 4.2 µg/kg/hr; maximal dose of 533.8 µg/kg/hr). Clinical, physiologic and laboratory data before, during and after infusion were analyzed.FindingsThe maximal tolerated dose for intravenous infusion of sodium nitrite was 267 µg/kg/hr. Dose limiting toxicity occurred at 446 µg/kg/hr. Toxicity included a transient asymptomatic decrease of mean arterial blood pressure (more than 15 mmHg) and/or an asymptomatic increase of methemoglobin level above 5%. Nitrite, nitrate, S-nitrosothiols concentrations in plasma and whole blood increased in all subjects and returned to preinfusion baseline values within 12 hours after cessation of the infusion. The mean half-life of nitrite estimated at maximal tolerated dose was 45.3 minutes for plasma and 51.4 minutes for whole blood.ConclusionSodium nitrite can be safely infused intravenously at defined concentrations for prolonged intervals. These results should be valuable for developing studies to investigate new NO treatment paradigms for a variety of clinical disorders, including cerebral vasospasm after subarachnoid hemorrhage, and ischemia of the heart, liver, kidney and brain, as well as organ transplants, blood-brain barrier modulation and pulmonary hypertension.Clinical Trial Registration Information http://www.clinicaltrials.gov; NCT00103025
Highlights
Sodium nitrite can be safely infused intravenously at defined concentrations for prolonged intervals. These results should be valuable for developing studies to investigate new nitric oxide (NO) treatment paradigms for a variety of clinical disorders, including cerebral vasospasm after subarachnoid hemorrhage, and ischemia of the heart, liver, kidney and brain, as well as organ transplants, blood-brain barrier modulation and pulmonary hypertension
There were 2 Caucasians and 10 African Americans; this did not reflect a normal population distribution, it was the effect of the consecutive subject recruitment
Sodium nitrite infusion and NO metabolome We present the results in 3 groups based on the dosing scheme of sodium nitrite
Summary
Intra-arterially delivered NO has been shown to prevent the development of delayed cerebral vasospasm after subarachnoid hemorrhage [4,5,6,7,8,9,10] in a primate model and to facilitate treatment of brain tumors in a rodent model [11] These preclinical findings have not been translated into effective clinical treatments, because safe and prolonged delivery of NO at therapeutic levels is not feasible using available systemic NO donors (nitroglycerin and nitroprusside) [4,9] as these organic nitrates have unpredictable pharmacokinetics, rapidly develop tolerance, and when discontinued, often evoke rebound effect unless delivered extravascularly or locally [12]. The study was developed to determine the safety and feasibility of prolonged sodium nitrite infusion
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
