This study revises the structure and expression of the BDNF gene in mice and rats, revealing that both species have eight 5' untranslated exons and one 3' protein-coding exon. The research identifies novel 5' untranslated exons and introduces a new numbering system for BDNF exons. BDNF transcripts are generated by splicing one of the eight 5' exons to the 3' coding exon, or by extending the 3' exon. The study also shows distinct tissue-specific expression profiles of the 5' exon-specific transcripts in various brain and non-neural tissues. Kainic acid-induced seizures, which alter intracellular calcium levels and inhibit DNA methylation and histone deacetylation, contribute to the differential regulation of BDNF transcripts. The study confirms that mouse and rat BDNF gene loci do not encode antisense mRNA transcripts, suggesting that the regulatory mechanisms of rodent and human BDNF genes differ significantly. The research also identifies new exons and provides insights into the regulation of BDNF gene expression by DNA methylation and histone deacetylation. The findings highlight the complexity of BDNF gene structure and expression, and the importance of understanding these mechanisms for understanding nervous system function and pathology.This study revises the structure and expression of the BDNF gene in mice and rats, revealing that both species have eight 5' untranslated exons and one 3' protein-coding exon. The research identifies novel 5' untranslated exons and introduces a new numbering system for BDNF exons. BDNF transcripts are generated by splicing one of the eight 5' exons to the 3' coding exon, or by extending the 3' exon. The study also shows distinct tissue-specific expression profiles of the 5' exon-specific transcripts in various brain and non-neural tissues. Kainic acid-induced seizures, which alter intracellular calcium levels and inhibit DNA methylation and histone deacetylation, contribute to the differential regulation of BDNF transcripts. The study confirms that mouse and rat BDNF gene loci do not encode antisense mRNA transcripts, suggesting that the regulatory mechanisms of rodent and human BDNF genes differ significantly. The research also identifies new exons and provides insights into the regulation of BDNF gene expression by DNA methylation and histone deacetylation. The findings highlight the complexity of BDNF gene structure and expression, and the importance of understanding these mechanisms for understanding nervous system function and pathology.