US researchers report that inducing hibernation among rats using an opioid drug has been found to reduce the damage caused by an artificial stroke in the animals.
Writing about their findings in the open access journal BMC Biology, researchers at the Florida-based University of South Florida Center for Aging and Brain Repair have revealed that the animals put into the chemical fugue suffered less behavioural dysfunctions after a period of cerebral artery blockage than control rats.
Cesar Borlongan, a neurologist at the university, worked with a team of researchers from the National Institutes of Health to investigate the role of the opioid system in brain injury and protection.
He said: "Studies in hibernating and active squirrels have shown that 'natural hibernation' has anti-ischemic effects. We've shown that a drug that induces hibernation can achieve similar results."
The researchers dosed the rats with [D-ala2,D-leU5]enkephalin (DADLE), a drug from the same pharmaceutical family as morphine and heroin.
They observed that, after an experimental stroke, the pre-treated animals performed better than control rats in a series of behavioural tests.
The researchers write: "DADLE prevented cell death processes and behavioral abnormalities. The observation that this substance, previously shown to induce hibernation, attenuated deficits inherent in cerebral ischemia provides a new pharmacological target for stroke therapy."