effects of cold injury on sensorimotor cortex of mouse brain

ABSTRACT

Cold injury has been used as a useful model for studies of traumatic brain injury. This model is used to induce brain edema. Brain edema is a pathophysiological condition of increased brain water content due to a variety of coexisting brain injuries, including ischemia, trauma, tumor and infection. The purpose of this study was to evaluate the effects of cold injury on sensorimotor cortex of mouse. 15 male NMRI mice, 6-8 weeks old every one of them with the weight of 30-35gr [5 mice per group] were studied. To produce cold injury a metal probe cooled with liquid nitrogen and was applied to the surface of the intact skull above the parietal lobe by force of 100 gr for 30 sec. Brains were removed 72h after cold injury, 10 micro m serial sections were obtained following fixation, processing and blocking of the brain. The sections were stained using creysl fast violet. Sensorimotor cortex was recognized and 35 fields were chosen randomly to be studied. To do morphometrical study on cortex of frontal and parietal lobes, the cells with a nucleus diameter of 10 micro m were determined. The data were analyzed by means of ANOVA and TUKEY'S HSD test. The results indicated that the number of alive neurons in the model group was significantly [p<0.05] lower than that of control groups. Cold injury decreases the number of normal cells of sensory motor cortex and leads to cell death