Expression and potential role of phospholipase D1 in cryoinjured cerebral cortex of rats
M.D. Kim1, D.S. Min2, K.B. Sim3, H.-J. Cho4 and T. Shin5
1Department of Psychiatry, College of Medicine, Cheju National University, Jeju, South Korea, 2Department of Molecular Biology, College of Natural Sciences, Pusan National University, Pusan, South Korea, 3Department of Neurosurgery, College of Medicine, Cheju National University, Jeju, South Korea, 4Department of Anatomy, School of Medicine, Kyungpook National University, Taegu, South Korea and 5Department of Veterinary Medicine, Cheju National University, Jeju, South Korea
Offprint requests to: Dr. Taekyun Shin, Department of Veterinary Medicine, Cheju National University, Jeju 690-756, South Korea. Fax: +86-64-756-3354. e-mail: shint@cheju.ac.kr
Summary. The expression and potential role of phospholipase D1 (PLD1) were studied in the cerebral cortex of rats after freeze injury. Histopathologically, cryoinjury, by exposing cerebral cortex to a prechilled rod for 1 minute, produced consistent pathological lesions, specifically neuronal death, infiltration of macrophages into the center of the cryoinjury, and reactive astrogliosis at the periphery, which caused the lesion site to become encased. Western blot analysis showed that PLD1 expression in the ipsilateral cerebral cortex increased significantly during days 1 to 3 after cryoinjury and declined slightly at post-injury day 7. PLD1 immunoreactivity was very low in the brains of sham-operated control adults. After cryoinjury, there was substantial PLD1 immunostaining of numerous inflammatory cells in the ipsilateral cortex, which were identical to ED1-positive macrophages. In addition, PLD1 immunoreactivity was increased in some neurons and astrocytes at the periphery of the cryoinjury at post-injury days 3 and 7. These findings suggest that cryoinjury by means of prechilled rods induced consistent histopathological changes in the cerebral cortex. In addition, expression of a cell activation signal, PLD1, was upregulated in macrophages and astrocytes in the ipsilateral cerebral cortex after cryoinjury. Histol Histopathol 19, 1015-1019 (2004)
Key words: Brain injury, Cryoinjury, Macrophage, Phospholipase D1
DOI: 10.14670/HH-19.1015