Immunohistochemical study on the distribution of nitrotyrosine and neuronal nitric oxide synthase in aged rat cerebellum.
In the present study, we examined age-related changes in 3-nitrotyrosine (NT) and neuronal nitric oxide synthase (nNOS) in rat cerebellum using immunohistochemistry. No immunoreactivity for NT was found in any layers of adult cerebellar cortex. In aged cerebellar cortex, the most prominent labeling of NT was found in the Purkinje cell layers and molecular layers. In aged cerebellar nuclei, NT immunoreactivity was observed in the surrounding neuropil. In aged rat cerebellum, nNOS immunoreactivity was significantly decreased in the molecular layer, while it was slightly increased in the granular layer. Image analysis showed no significant age-related changes in nNOS immunoreactivity in the cerebellar nuclei. In summary, this report has demonstrated that NT increases with age in the cerebellum, and suggests that NO production by the neuronal form of NOS may not be the rate limiting step in NT formation in the aged brain. Further work is needed to examine the mechanisms underlying the increased immunoreactivity for NT, and the functional implications of this increase.
Chung
Yoon Hee
YH
Department of Anatomy, Seoul National University College of Medicine, 28 Yongon-Dong, Chongno-Gu, Seoul 110-799, South Korea.
Shin
Chung Min
CM
Joo
Kyeung Min
KM
Kim
Myeung Ju
MJ
Cha
Choong Ik
CI
D000375:Aging / Q000378:metabolism*; D000818:Animals; D002525:Cerebellar Cortex / Q000187:drug effects / Q000378:metabolism; D002531:Cerebellum / Q000166:cytology / Q000201:enzymology / Q000378:metabolism*; D007091:Image Processing, Computer-Assisted; D007150:Immunohistochemistry; D009474:Neurons / Q000201:enzymology / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D052248:Nitric Oxide Synthase Type I; D011689:Purkinje Cells / Q000201:enzymology / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000378:metabolism*; D015854:Up-Regulation
C002744:3-nitrotyrosine; D014443:Tyrosine; D019001:Nitric Oxide Synthase; D052248:Nitric Oxide Synthase Type I; C496322:Nos1 protein, rat