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bioRxiv · 10.1101/2022.02.14.480371

The impacts of anesthetic regimens on the middle cerebral artery occlusion outcomes in male rats

Abstract

ObjectivesThe middle cerebral artery occlusion (MCAO) model was introduced more than three decades ago to simulate human stroke. Till now, it is the most common platform to investigate stroke-induced pathological changes as well as discover new drugs and treatments. Induction of general anesthesia is mandatory to induce this model, and different laboratories are using various anesthetic drugs, which might affect MCAO results. Therefore, the present study was designed to compare the impacts of several widely used anesthetic regimens on the MCAO outcomes. Materials and MethodsHere, adult male rats were anesthetized by isoflurane inhalation, intraperitoneal injection of chloral hydrate, intraperitoneal injection of ketamine-xylazine, or subcutaneous administration of ketamine-xylazine, then subjected to 30 min MCAO. Mortality rate, body weight change, infarct size, as well as cognitive and neurological performance were evaluated up to three days after the surgery. ResultsOur findings revealed chloral hydrate caused the highest, while subcutaneous ketamine-xylazine led to the lowest mortality rate. Meanwhile, there were no significant differences in the body weight loss, infarct size, cognitive impairments, and neurological deficits among the experimental groups. ConclusionsBased on the current results, we proposed that subcutaneous injection of ketamine-xylazine could be an effective anesthetic regimen in the rat model of MCAO with several advantages such as low mortality, cost-effectiveness, safety, ease of administration, and not requiring specialized equipment.

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BibTeXRIS

Mousavi, S. M., Karimi-Haghighi, S., Chavoshinezhad, S., Pandamooz, S., Belem-Filho, I. J. A., Keshavarz, S., Bayat, M., Hooshmandi, E., Rahimi Jaberi, A., Salehi, M. S., Borhani-Haghighi, A.. 2022-02-16. The impacts of anesthetic regimens on the middle cerebral artery occlusion outcomes in male rats. https://doi.org/10.1101/2022.02.14.480371

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