Opioid receptor agonists reduce brain edema in stroke
Li Yang1, Hezhen Wang, Kaushik Shah
1Department of Pharmaceutical Sciences, School of Pharmacy, Texas Tech University Health Sciences Center, 1300 S Coulter Drive, Amarillo, TX 79106, USA.
Brain Research
|February 2, 2011
Summary
Biphalin, a non-selective opioid agonist, effectively reduced brain edema and infarct size in stroke models. This suggests opioid receptor activation may offer neuroprotection and warrants further investigation for stroke treatment.
Area of Science:
- Neuroscience
- Pharmacology
- Stroke Research
Background:
- Cerebral edema is a major cause of mortality in stroke patients.
- Opioid receptors are implicated in neurological functions and potential neuroprotection.
Purpose of the Study:
- To evaluate the efficacy of biphalin, a non-selective opioid receptor agonist, in mitigating brain edema formation in stroke models.
- To compare biphalin's anti-edematous effects with selective opioid agonists.
Main Methods:
- In vitro: Hippocampal slices exposed to oxygen-glucose deprivation (OGD) to induce ischemia.
- In vivo: Permanent middle cerebral artery occlusion (MCAO) model in rodents.
- Assessment of water content, cell volume, infarct size, and neuronal recovery.
Main Results:
- Biphalin significantly reduced water content in OGD-exposed hippocampal slices, outperforming selective mu, delta, and kappa opioid agonists.
- Biphalin demonstrated dose-dependent anti-edematous effects, confirmed by naloxone reversal, indicating opioid receptor mediation.
- In the MCAO model, biphalin significantly decreased edema (53%), infarct ratios (48%), and improved neuronal recovery.
Conclusions:
- Opioid receptor activation, particularly with non-selective agonists like biphalin, shows significant neuroprotective potential against ischemic stroke.
- Biphalin's ability to reduce edema and infarct size suggests its promise as a therapeutic agent for stroke.
- Further research into novel opioid agonists is warranted for developing effective stroke treatments.
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