[Possible involvement of histone acetylation in the development of emotional resistance to stress stimuli].

Recent research has demonstrated that complex 'epigenetic' mechanisms, which regulate gene transcription without altering the DNA code, could play a critical role in the pathophysiology of psychiatric disorders. We previously reported that pretreatment of mice with 5-HT(1A) receptor agonists 24 hr before testing suppressed the decrease in emotional behaviors induced by exposure to acute restraint stress. In addition, DNA microarray analysis showed that such a pretreatment with 5-HT(1A) receptor agonist produces changes in several gene transcriptions in the hippocampus including the reduction of histone deacetylase 10. Based on these findings, we recently carried out studies focused on the relationship between the development of emotional resistance to stress and histone acetylation induced by a 5-HT(1A) receptor agonist as well as a histone deacetylase inhibitor. The findings suggest that 5-HT(1A) receptor agonists may be useful for preventing mental illnesses that arise due to a decreased resistance and adaptability to stress. Moreover, the notion that chromatin remodeling is an important mechanism in mediating emotionality under stressful situations is further supported.