Evaluation of temperature induction in focal ischemic thermocoagulation model

Author(s)

da Silva, Helio ^{[1, 2]} ; Nucci, Mariana P. ^[3] ; Mamani, Javier B. ^[2] ; Mendez-Otero, Rosalie ^[4] ; Nucci, Leopoldo P. ^{[5, 2]} ; Tannus, Alberto ^[6] ; Gamarra, Lionel F. ^{[1, 2]}

Affiliation

^[1] Santa Casa Misericordia Sao Paulo, Sao Paulo - Brazil

^[2] Hosp Israelite Albert Einstein, Sao Paulo - Brazil

^[3] Univ Sao Paulo, Hosp Clin HCFMUSP, Sao Paulo, SP - Brazil

^[4] Univ Fed Rio de Janeiro, Inst Biofis Carlos Chagas Filho, Rio de Janeiro - Brazil

^[5] Univ Fed Sao Paulo, Sao Paulo - Brazil

^[6] Univ Sao Paulo, CIERMag Inst Fis Sao Carlos, Sao Paulo - Brazil

• Document type: Journal article
• Source: PLoS One; v. 13, n. 7 JUL 5 2018.
• Web of Science Citations: 1

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 degrees C, 300 degrees C, and 400 degrees 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 degrees C and 400 degrees 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 degrees C causes permanent ischemic stroke and motor deficit. (AU)

• FAPESP's process: 16/21470-3 - Therapeutic action of mesenchymal stem cells from human bone marrow labeled with multimodal nanoparticles in diabetic rats subjected to stroke: study of cellular, molecular and functional mechanisms.
• Grantee: Lionel Fernel Gamarra Contreras
• Support Opportunities: Regular Research Grants
• FAPESP's process: 14/50983-3 - INCT 2014: complex fluids
• Grantee: Antonio Martins Figueiredo Neto
• Support Opportunities: Research Projects - Thematic Grants