Hydrogen inhalation attenuates oxidative-stress-related endothelial injury after subarachnoid hemorrhage in rats
Zhuang Z et al. · Front Neurosci. 2020;13:1441.
What kind of evidence is this?
Preclinical
Multi-part controlled rat subarachnoid-hemorrhage experiment comparing exposure durations and repeated dosing
Other neurological conditions
Inhaled H₂
Not reported in this record.
Not reported in this record.
Methods at a glance
182 male Sprague-Dawley rats with endovascular-perforation subarachnoid hemorrhage or sham surgery
182 rats across several experiments; principal comparisons commonly used n=6 per group
Single exposure or daily exposure for 3 or 7 days, depending on experiment
3.3% H₂ inhalation beginning 30 minutes after hemorrhage for 30, 60 or 120 minutes; selected protocols were repeated daily
H₂ diluted in chamber air with oxygen adjusted separately — not Brown’s gas.
3.3% H₂; chamber O₂ maintained at 21%.
Not reported — chamber concentration is given, but H₂ flow in mL/min is not.
21% O₂ was maintained using supplemental oxygen; O₂ flow in mL/min was not reported.
Room-air chamber exposure after hemorrhage and sham controls
Outcomes and reported result
Brain edema, blood-brain barrier, oxidative and inflammatory markers, microthrombosis, vasospasm and short- and long-term neurological behavior
The article reports lower vascular inflammatory and apoptotic markers, edema, microthrombi and vasospasm and improved neurological outcomes with selected H₂ schedules.
Gas composition, allocation structure, methods and principal results checked in the open-access full text.
A reported association, difference or mechanism is not automatically a clinical benefit. Null findings, outcome type, study design and precision all matter.
Cautions and applicability
Large total animal number spread across many experiments, exposure schedules and molecular outcomes; no human participants.
Experimental subarachnoid hemorrhage in rats.
Not reported in this record.
Not reported in this record.
Not reported in this record.
No single-study GRADE certainty rating is assigned. Certainty is assessed by important outcome across a complete eligible evidence set, not by attaching a final grade to one source.
Sources and record status
PMID: 32038143 · DOI: 10.3389/fnins.2019.01441
Open-access full text is available through PMC and Frontiers.
Open-access PMC/Frontiers full text and PubMed record.
2026-08-10