FIGURE 7.

iPLA₂β protein expression levels are higher in late passage than in early passage VSMC and can be further up-regulated by TNF-α in cultured VSMC. A, representative Western blots show expressions of iPLA₂β, SM22α, SMαA, and GAPDH in cultured early and late passage aortic VSMC isolated from mice (5 passage versus 10 passages), rats (1 passage versus 9 passages), and rabbit (2 passage versus 9 passages). E, early passage; L, late passage. B, summary of a 0.952-kb mouse iPLA₂β promoter activity in cultured early and later rat aortic VSMC (2 passage versus 9 passages). ***, p < 0.001 versus early passage VSMC. C, representative iPLA₂β Western blots from rat aortic VSMC stimulated with or without TNF-α (10 ng/ml, 24 h). D, quantitative data shown in C. n = 8.