534 Aid et al. exon VIII (exon VII according to Liu et al.) is driven by a separate promoter. Liu and colleagues’ data argue that tran- scripts containing exons VII and VIII (exons VI and VII according to Liu et al.) share the same promoter. 4) Our expression analysis data for all BDNF transcripts includes a wider range of tissues and brain structures analyzed both in rat and in mouse. 5) Liu et al. studied the regulation of some BDNF transcript expression in brain upon adminis- tration of cocaine. Our data show activity-dependent reg- ulation of rat BDNF mRNAs by kainic acid-induced seiz- ures in rat hippocampus. Moreover, we report differential regulation of the expression of BDNF transcripts by DNA methylation and histone deacetylation. 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