TY - JOUR T1 - Developmental changes in brain HDAC activity in rodents and non-human primates measured by [<sup>18</sup>F]FAHA-PET JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 1771 LP - 1771 VL - 51 IS - supplement 2 AU - Hiroshi Mizuma AU - Ryuichi Nishii AU - Shinya Kagawa AU - Akiko Tachibana AU - Kazuhiro Takahashi AU - Yasuhisa Tamura AU - Tatsuya Higashi AU - Juri Gelovani AU - Hirotaka Onoe Y1 - 2010/05/01 UR - http://jnm.snmjournals.org/content/51/supplement_2/1771.abstract N2 - 1771 Objectives Histone deacetylase (HDAC) plays a key role in regulation of gene expression via chromatin remodeling. 6-([18F]fluoroacetamide)-1-hexanoicanilide ([18F]FAHA) is an analog of HDAC inhibitor, SAHA, and is developed to measure the histone deacetylase (HDAC) activity in vivo using PET. To study the role of HDAC in brain growth and maturation, we here measured the developmental changes in HDAC activity in the brain by PET with [18F]FAHA. Methods [18F]FAHA was synthesized according to the methods developed in our group in high specific activity (&gt;74 GBq/μM). Brain HDAC activities were measured at infant, adolescent, adult, and aged periods (at 4, 8, 24, and 96 weeks of age in Wistar rats, and at 9, 24, and 60 months of age in macaque monkeys). [18F]FAHA (rats, 150 MBq/kg; monkeys, 37 MBq/kg) was intravenously injected, and the emission data were then acquired for 60 min using microPET focus220. After the PET scan, ex vivo autoradiography was performed in rats to assess the regional detailes of [18F]FAHA uptake. Results A gradual increase in cerebral uptake of [18F]FAHA was observed from infantile to adult period at which it was reached to the maximum level. In rats, decrease in the uptake of [18F]FAHA was observed at aged period compared with that of adulthood. The regional uptake of [18F]FAHA showed higher uptake in the cerebral cortex and striatum than that in other brain regions. Conclusions Dynamic PET imaging with [18F]FAHA indicate that the age-related changes in HDAC activity may play an important role in the development and function of brain ER -