Abstract |
Adenylate cyclase (AC) has a specific sensitivity to Ca2+/ calmodulin. AC-I, one of the mediator of learning and memory, plays an important role in signal transduction underlying learning and memory function. In the present study, we found ischemia-related changes of AC-I in the hippocampal CA1 region, but not in the CA2/3 region, after 5 min of transient forebrain ischemia in gerbils. In the sham-operated group, AC-I immunoreactive neurons were detected in pyramidal and non-pyramidal cells in the hippocampus proper. AC-I immunoreactivity was significantly increased at 3 h in the CA1 region after ischemic insult. Thereafter, AC-I immunoreactivity was gradually decreased. Four days after ischemic insult, AC-I-immunoreactive CA1 pyramidal cells in the stratum pyramidale were very few due to delayed neuronal death. The results of Western blot analysis showed that changes of AC-I protein contents were similar to immunohistochemical data after ischemic insult. Gpp(NH)p-dependent AC-I activity in hippocampal CA1 region was not changed in all groups, while Ca2+/ calmodulin-dependent AC-I activity in hippocampal CA1 region was significantly decreased 24 h after ischemia-reperfusion. These results suggest that the decrease of AC-I activity may be associated with impairment of neurodevelopment and neuroplasticity including learning and memory although the AC-I immunoreactivity was maintained 24 h postischemic group compared to that of the sham-operated group.
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Authors | In Koo Hwang, Ki-Yeon Yoo, Young-Sil Kim, Boo Kyoung Jung, Hua Li, Do-Hoon Kim, Tae-Cheon Kang, Hyung-Cheul Shin, Moo Ho Won |
Journal | Journal of the neurological sciences
(J Neurol Sci)
Vol. 240
Issue 1-2
Pg. 93-8
(Jan 15 2006)
ISSN: 0022-510X [Print] Netherlands |
PMID | 16297936
(Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
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Topics |
- Adenylyl Cyclases
(metabolism)
- Analysis of Variance
- Animals
- Blotting, Western
(methods)
- Disease Models, Animal
- Gerbillinae
- Hippocampus
(enzymology, pathology)
- Immunohistochemistry
(methods)
- Ischemic Attack, Transient
(metabolism, pathology)
- Male
- Neurons
(metabolism)
- Reperfusion
- Staining and Labeling
(methods)
- Time Factors
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