J Vet Sci. 2007 Dec;8(4):323-327   
 

Increased phosphorylation of caveolin-1 in the spinal cord of irradiated rats

Heechul Kim1,2,3,¢Ó, Changjong Moon4,¢Ó, Jeongtae Kim1, Meejung Ahn1,2,3, Jin Won Hyun2,5, Jae Woo Park2,6, Sung-Ho Kim4, Seungjoon Kim2, Taekyun Shin1,2,3,*
 

1Department of Veterinary Medicine, College of Applied Life Sciences, 2Applied Radiological Science Research Institute, 3Research Institute for Subtropical Agriculture and Biotechnology, 5Department of Biochemistry, College of Medicine, and 6Department of Nuclear and Energy Engineering, College of Engineering, Cheju National University, Jeju 690-756, Korea 4Department of Veterinary Anatomy, College of Veterinary Medicine, Chonnam National University, Gwangju 500-757, Korea
* shint@cheju.ac.kr
 

Phosphorylation of caveolin-1 occurs during cell activation by various stimuli. In this study, the involvement of caveolin-1 in an irradiation injured spinal cord was examined by analyzing the phosphorylation of caveolin-1 in the spinal cord of rats after irradiation with a single dose of 15 Gray from a 60Co ¥ã-ray source at 24 h post-irradiation (PI). A Western blot analysis showed that the phosphorylated form of caveolin-1 (p-caveolin-1) was expressed constitutively in the normal spinal cords and was significantly higher in the spinal cord of irradiated rats at 24 h PI. The increased expression of ED1, which is a marker of activated microglia/macrophages, was matched with that of p-caveolin-1. In the irradiated spinal cords, there was a higher level of p-caveolin-1 immunoreactivity in the isolectin B4-positive microglial, ependymal, and vascular endothelial cells, in which p-caveolin-1 was weakly and constitutively expressed in the normal control spinal cords. These results suggest that total body irradiation induces activation of microglial cells in the spinal cord through the phosphorylation of caveolin-1.