Studies of ischemic brain injury are an important area of modern biomedical research. So far, a lot of ischemic stroke models have been proposed, along with different imaging and staining modalities aimed to visualize the damaged tissue. In this work we use a rat model to investigate how the experimental setup affects the interpretation of experimental data obtained in the acute phase of ischemic stroke (5 hours after the occlusion of the middle cerebral artery). We show the association between the choice of the type of anesthesia and the severity of ischemic injury: in our experiments brain damage was the most pronounced in the animals anesthetized with a combination of chloral hydrate and Rometar; the least damage was observed for isoflurane. Staining was performed using the popular dye 2,3,5-triphenyltetrazolium chloride (TTC). We demonstrate that parameters of brain slices incubation in TTC also need to be accounted for when interpreting the results obtained during the acute phase of stroke, the optimum incubation time being 30 min and temperature 37 °С.