title: Comparison of GAD65 and 67 immunoreactivity in the lumbar spinal cord between young adult and aged dogs.
abstract: We investigated distribution and age-related changes in two isoforms of GABA synthesizing enzymes, glutamic acid decarboxylase (GAD) 65 and 67, in the lumbar levels (L(5)-L(6)) of the dog spinal cord. Male German shepherds were used at 1-2 years (young adult dogs) and 10-12 years (aged dogs) of age. GAD65 immunoreaction was observed in neuropil, not in cell bodies, in all laminae of the adult lumbar spinal cord: Many punctate GAD65-immunoreactive structures were shown in all laminae. The density of GAD65 immunoreactive structures was highest in laminae I-III, and lowest in lamina VII. In the aged dog, the distribution pattern of GAD65 immunoreactivity was similar to that in the adult dog; however the density of GAD65-immunoreactive structures and its protein levels were significantly increased in the aged lumbar spinal cord. GAD67 immunoreaction in the adult dog was also distributed in all laminae of the lumbar spinal cord like GAD65; however, we found that small GAD67-immunoreactive cell bodies were observed in laminae II, III and VIII. In the aged dogs, GAD67 immunoreactivity and its protein levels were also increased compared to those in the adult group. In conclusion, our results indicate that the distribution of GAD65-immunoreactive structures is different from GAD67-immunoreactive structures and that their immunoreactivity in the aged dogs is much higher than the adult dogs.
authors.affiliation: Department of Physiology, and Institute of Neurodegeneration and Neuroregeneration, College of Medicine, Hallym University, Chuncheon, 200-702, South Korea.
authors.forename: Hyun Joo
authors.initials: HJ
authors.lastname: Lee
authors.forename: Jung Hoon
authors.initials: JH
authors.lastname: Choi
authors.forename: Ji Hyeon
authors.initials: JH
authors.lastname: Ahn
authors.forename: Choong Hyun
authors.initials: CH
authors.lastname: Lee
authors.forename: Ki-Yeon
authors.initials: KY
authors.lastname: Yoo
authors.forename: In Koo
authors.initials: IK
authors.lastname: Hwang
authors.forename: Jin Sang
authors.initials: JS
authors.lastname: Kim
authors.forename: Choonghyo
authors.initials: C
authors.lastname: Kim
authors.forename: Yun Lyul
authors.initials: YL
authors.lastname: Lee
authors.forename: Hyung-Cheul
authors.initials: HC
authors.lastname: Shin
authors.forename: Moo-Ho
authors.initials: MH
authors.lastname: Won
mesh_terms: D000367:Age Factors; D000818:Animals; D004285:Dogs; D005968:Glutamate Decarboxylase / Q000378:metabolism*; D007150:Immunohistochemistry; D007527:Isoenzymes / Q000378:metabolism*; D008159:Lumbar Vertebrae; D008297:Male; D013116:Spinal Cord / Q000166:cytology / Q000378:metabolism*
chemical_list: D007527:Isoenzymes; D005968:Glutamate Decarboxylase; C402565:glutamate decarboxylase 1; C401141:glutamate decarboxylase 2