Hyperbaric oxygen therapy in experimentally induced acute cerebral ischemia

Area of Science:

• Neuroscience
• Hyperbaric Medicine
• Ischemic Stroke Research

Background:

• Acute cerebral ischemia, a critical condition, poses significant challenges in treatment and recovery.
• Spontaneously hypertensive rats are a relevant model for studying cerebrovascular diseases.
• Hyperbaric oxygen (HBO) therapy is being explored for its potential therapeutic effects in ischemic conditions.

Purpose of the Study:

• To investigate the efficacy of hyperbaric oxygen (HBO) therapy in mitigating the effects of acute cerebral ischemia.
• To determine the optimal timing for HBO administration following ischemic events.
• To assess the impact of HBO on survival rates and brain tissue metabolites in an ischemic rat model.

Main Methods:

• Bilaterally ligating carotid arteries in spontaneously hypertensive rats to induce cerebral ischemia.
• Administering HBO (100% O2 at 2 ATA for 30 min) at 1 or 3 hours post-ligation.
• Measuring survival time and key brain tissue metabolites (lactate, ATP) in treated and untreated (ischemic) groups.

Main Results:

• HBO treatment initiated 3 hours after ischemia significantly prolonged survival time (6.5 vs. 4.3 hours) and reduced cerebral lactate accumulation (24.60 vs. 31.78 mM/kg).
• A trend towards less ATP depletion was observed in the 3-hour HBO-treated group.
• No significant differences in survival or metabolites were found when HBO was administered 1 hour after ischemia.

Conclusions:

• Hyperbaric oxygen therapy, when administered 3 hours post-ischemia, demonstrates a therapeutic benefit by reducing cerebral lactate and increasing survival.
• The timing of HBO administration is critical for its effectiveness in acute cerebral ischemia.
• Further research into HBO's neuroprotective mechanisms and optimal treatment windows is warranted.