Evaluation of temperature induction in focal ischemic thermocoagulation model

Abstract

The thermocoagulation model, which consists of focal cerebral ischemia with craniectomy, is helpful in studying permanent ischemic brain lesions and has good reproducibility and low mortality. This study analyzed the best conditions for inducing a focal ischemic lesion by thermocoagulation. We investigated parameters such as temperature and thermal dissipation in the brain tissue during induction and analyzed real-time blood perfusion, histological changes, magnetic resonance imaging (MRI), and motor behavior in a permanent ischemic stroke model. We used three-month-old male Wistar rats, weighing 300–350 g. In the first experiment, the animals were divided into four groups (n = 5 each): one sham surgery group and three ischemic lesion groups having thermocoagulation induction (TCI) temperatures of 200°C, 300°C, and 400°C, respectively, with blood perfusion (basal and 30 min after TCI) and 2,3,5-Triphenyl-tetrazolium chloride (TTC) evaluation at 2 h after TCI. In the second experiment, five groups (n = 5 each) were analyzed by MRI (basal and 24 h after TCI) and behavioral tests (basal and seven days after TCI) with the control group added for the surgical effects. The MRI and TTC analyses revealed that ischemic brain lesions expressively evolved, especially at TCI temperatures of 300°C and 400°C, and significant motor deficits were observed as the animals showed a decrease frequency of movement and an asymmetric pattern. We conclude that a TCI temperature of 400°C causes permanent ischemic stroke and motor deficit.

Triple-modal imaging of stem-cells labeled with multimodal nanoparticles, applied in a stroke model

“…Induction of a focal ischemic lesion via thermocoagulation (stroke): A focal brain ischemic lesion was induced via thermocoagulation in the pial blood vessels of the motor and somatosensory cortex as previously described[21]. Briefly, animals were anesthetized with ketamine hydrochloride (100 mg/kg, i.p.)…”

“…The ischemic lesion was confirmed through local blood perfusion analysis using a PeriCam Perfusion Speckle Imager (PSI) system (Perimed, Stockholm, Sweden) and TTC staining after 2 h of lesion induction, as described in a previous study[21]. The color changes of the targeted region, from light red to dark red, were also noted[22].…”

Comparative effects of dexmedetomidine and propofol on brain and lung damage in experimental acute ischemic stroke

“…to bregma). Transdural thermocoagulation of blood in the superficial vessels was performed by approaching a hot probe adjusted to 300 °C temperature 39 . Vessel lesions were evaluated macroscopically through the colour changes after 5 min.…”

Functional Recovery Caused by Human Adipose Tissue Mesenchymal Stem Cell-Derived Extracellular Vesicles Administered 24 h after Stroke in Rats

“…Animals were randomly allocated to three treatment groups: sham, ischemic (ISC), and ischemic treated with EVs (ISC + EV). Our stroke model of focal cerebral permanent ischemia represents a protocol to investigate brain lesions with good reproducibility and low mortality [ 17 , 18 , 19 , 20 , 21 , 50 , 68 , 69 ].…”