Age-related changes of cornu ammonis 1 pyramidal neurons in gerbil transient ischemia.
This study reports that postischemic apoptotic cell death of the hippocampal cornu ammonis (CA) 1 neurons is delayed in aged gerbils. Age-related changes in the process of CA1 neuronal death following transient ischemia was studied. Two groups of Mongolian gerbils were used in this study, which compared adult (4-month-old) and aged (24-month-old) animals by hematoxylin-eosin stain, in situ nick-end labeling (TUNEL method) and electron microscopy. In the process of neuronal death, neuronal loss of the aged group was histologically less severe than that of the adult group. TUNEL-positive cells were found on days 3-5 after ischemia in the adult group, while they were still found on day 7 in the aged group. The apoptotic process of the aged group was delayed compared to the adult group. Furthermore, lipofuscin was ultrastructurally observed inside the apoptotic body 5 days after ischemia in CA1 pyramidal neurons of the aged group. It is likely that colocalization of lysosomal enzyme cathepsin D with lipofuscin might be associated with the age-related alteration of lysosomal system in the neurons. Altogether these data suggest that age-related lysosomal changes might affect the apoptotic cascade process in postischemic CA1 neurons.
Tamagaki
C
C
Department of Neuropsychiatry, Kansai Medical University, Osaka, Japan. tamagaki@takii.kmu.ac.jp
Murata
A
A
Asai
S
S
Takase
K
K
Gonno
K
K
Sakata
T
T
Kinoshita
T
T
D000375:Aging / Q000473:pathology*; D000818:Animals; D002402:Cathepsin D / Q000378:metabolism; D002452:Cell Count; D004801:Eosine Yellowish-(YS); D005849:Gerbillinae; D006416:Hematoxylin; D006624:Hippocampus / Q000378:metabolism / Q000473:pathology* / Q000648:ultrastructure; D020287:In Situ Nick-End Labeling / Q000706:statistics & numerical data; D002546:Ischemic Attack, Transient / Q000473:pathology* / Q000503:physiopathology; D008062:Lipofuscin / Q000378:metabolism; D017966:Pyramidal Cells / Q000473:pathology* / Q000648:ultrastructure; D013997:Time Factors
D008062:Lipofuscin; D002402:Cathepsin D; D004801:Eosine Yellowish-(YS); D006416:Hematoxylin