Characterization of Photothrombotic Cerebral Infarction Model At Sensorimotor Area of Functional Map in Rat

Abstract

Purpose: The purpose of this study is to induce a photothrombotic cerebral infarction (PTCI) model with sensorimotor dysfunction in rats with a cortical functional map and to find the time course of neurological and morphological changes. Methods: Using sixteen rats, a PTCI was produced by using an intravenous injection of rose bengal dye (20mg/kg) and exposed to cold light for 20 min at a position of 1 mm anterior to bregma and 3.5 mm right lateral of midline, with the help of a cortical functional map. Serial changes were evaluated in magnetic resonance images, in neurology by Rota-rod test (RRT) and Dynamic Plantar Aesthesiometer (DPA), and in pathology over time from day 1 through 14. Results: The brain infarction was successfully induced in all 16 rats without a single death. Infarction volume was reduced gradually over time from 147 mm(3) to 100, 47, 35, and 27 mm3 on days 1, 3, 7, 11, and 14 respectively. By RRT evaluation, significant increased neurological dysfunction from 41% to 49% was observed in 2 weeks. A DPA examination revealed a dysfunction of contralateral forelimb from 181% to 163% within 2 weeks. Hemorrhage and liquefaction were observed by MRI and histopathology. Conclusions: Sensorimotor dysfunction continued for 2 weeks in the PTCI model by targeting relevant cortex areas in the rat brain guided by a cortical functional map.