Comparison of anesthetic effects of isoflurane used alone or combined with xylazine on induced cerebral ischemia

Abstract

Intraluminal suture method of middle cerebral artery occlusion (MCAo) has been extensively used in ischemic stroke study. Although the MCAo model has several advantages in comparing different stroke model, it has time‐consuming demands and requires high level of surgical skill. Low mortality and reproducible infarct size in MCAo model are affected by surgical technique, environmental variation and prolonged duration of surgery. The purpose of this study was to determine the effect of anesthetics during prolonged experimental surgery on reproducible stroke model. Animals were subjected to MCAo using intraluminal suture method and provide with isoflurane anesthesia or combined xylazine sedation (20 mg/kg). Animals were randomly divided into three groups: no anesthesia groups (control), inhaled anesthetics groups (isoflurane), inhaled anesthetics combined sedative group (isoflurane + xylazine). Inhaled anesthetics group was provided isoflurane during MCAo surgery (20 min), post‐occlusion period (60 min) and reperfusion (5–10 min), thus total duration of inhaled anesthesia was about 90 min. Inhaled anesthetics combined sedative groups was provided isoflurane during MCAo surgery (20 min) and reperfusion (5–10) min. Xylazine (20 mg/kg) was administered 5 min prior to MCAo and 30 min after MCAo by intramuscular injection. That total duration of inhaled anesthesia was about 30 min. Inhaled anesthetics group that anesthetized during all the post‐occlusion period demonstrated a poor prognosis and high mortality rate compared with control and inhaled anesthetics combined xylazine group. Although the stable respiration signal was shown without abnormal thorax movement, brain infarct size and neurologic deficits revealed no difference between groups. Our results indicated that a modified method of inhalation anesthesia combined xylazine sedation could improve the reproducibility of stroke model and reduce the risk of mortality.Support or Funding InformationFunding: NRF‐2013R1A2A2A01067169, NRF‐2017R1A2A2A01067169, KRIBB‐KGM4611714This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.