while the unsaturated fatty acid may be oxidized in either the endothelial cell or smooth muscle cell , the lability of the endothelial relaxant factor suggests that at least some of this processing occurs before its release from the endothelium . the model in figure 1 suggests that an oxidized fatty acid or a derived free radical is responsible for activation of smooth muscle guanylate cyclase and increases in cyclic gmp levels .
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smooth muscle cell
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smooth muscle