Fang et al., investigated the effect of DHE on the protein phosphatase (PP)-2A and the PP-1 inhibitor calyculin A (CA)-induced AD-like tau hyperphosphorylation, and its involvement in PP-2A content in metabolically competent rat brain slices (Table 2) (Fang et al., 2007). This evidence concerns the gene PTPA and Alzheimer disease.