Inhalation of hydrogen gas attenuates ouabain-induced auditory neuropathy in gerbils
Qu J, Gan YN, Xie KL, Liu WB, Wang YF, Hei RY, Mi WJ, Qiu JH. · Acta Pharmacologica Sinica. 2012;33(4):445.
What kind of evidence is this?
Preclinical
Randomized four-group gerbil auditory-neuropathy experiment with H₂ concentration comparison
Other neurological conditions
Inhaled H₂
Not reported in this record.
Not reported in this record.
Methods at a glance
Male Mongolian gerbils aged 4–8 months after local round-window ouabain exposure.
Main outcomes used n=6 per group for saline, saline plus H₂, ouabain, and ouabain plus H₂. The article does not state one total across all 1%, 2% and 4% concentration experiments.
Two 60-minute exposures at one and six hours; apoptosis at 24 hours and hearing, hair-cell and ganglion outcomes at seven days.
One-hour chamber inhalation at one and six hours after ouabain or saline; 1%, 2% and 4% H₂ were compared, with 2% used for the principal mechanistic assessments.
H₂ delivered in air with oxygen held at 21% — not Brown's gas.
Total chamber flow was 4 L/min and O₂ was maintained at 21%. Direct calculations give H₂ flows of 40, 80 and 160 mL/min for 1%, 2% and 4% H₂, respectively, and O₂ flow of 840 mL/min.
40 mL/min at 1%; 80 mL/min at 2%; 160 mL/min at 4%.
840 mL/min, based directly on 21% of the reported 4 L/min total flow.
Saline, saline plus H₂, and ouabain without H₂; animals without H₂ were exposed to room air in the chamber.
Outcomes and reported result
Click and tone-burst auditory brainstem responses, distortion-product otoacoustic emissions, spiral-ganglion morphology and density, hair-cell morphology, TUNEL apoptosis and caspase-3.
2% and 4% H₂ reduced auditory-brainstem threshold shifts, while 1% did not show the same marked effect. H₂ improved spiral-ganglion morphology/density and reduced apoptosis. H₂ did not change hearing thresholds in saline animals, DPOAE amplitudes or hair-cell morphology; ouabain itself also left those hair-cell measures unchanged.
The complete free PMC article was checked for randomization, concentration comparison, total flow, directly calculated H₂/O₂ flows, timing, blinded histology, positive and null findings, funding and available disclosures.
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
Small outcome-specific groups, no overall total across concentration cohorts, animal toxin model rather than diverse human auditory neuropathies, short seven-day follow-up and no direct oxidative/inflammatory measurements. Chinese national public grants funded the work; no explicit conflict statement was identified, so absence is not inferred.
Experimental ouabain-induced auditory neuropathy in gerbils; it does not establish treatment for human hearing disorders.
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: 22388074 · DOI: 10.1038/aps.2011.190
Free full article in PubMed Central.
Complete PMC article and PubMed metadata; full-text extraction checked 9 August 2026.
2026-08-10