Proline-rich Akt substrate of 40-kDa (PRAS40) is one of the important interactive linkers between Akt and mTOR signaling pathways. The increase of PRAS40 is related with the reduction of brain damage induced by cerebral ischemia. In the present study, we investigated time-dependent changes in PRAS40 and phospho-PRAS40 (p-PRAS40) immunoreactivities in the hippocampal CA1 region of the gerbil after 5 min of transient cerebral ischemia. PRAS40 immunoreactivity in the CA1 region was decreased in pyramidal neurons from 12 h after ischemic insult in a time-dependent manner, and, at 5 days post-ischemia, PRAS40 immunoreactivity was newly expressed in astrocytes. p-PRAS40 immunoreactivity in the CA1 pyramidal neurons was hardly found 12 h and apparently detected again 1 and 2 days after ischemic insult. At 5 days post-ischemia, p-PRAS40 immunoreactivity in the CA1 pyramidal neurons was not found. These results indicate that ischemia-induced changes in PRAS40 and p-PRAS40 immunoreactivities in CA1 pyramidal neurons and astrocytes may be closely associated with delayed neuronal death in the hippocampal CA1 region following transient cerebral ischemia.
PRAS40 Transient global cerebral ischemia Delayed neuronal death Astrocyte
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The authors would like to thank Mr. Seung Uk Lee for technical help. This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2014R1A1A2058440), by a Grant HO14C0001 from Osong Innovation Center funded by the Ministry of Health & Welfare, the Republic of Korea, and by 2013 Research Grant from Kangwon National University (No. 120131326).
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Disclosure of potential conflicts of interest
The authors declare that they have no potential conflicts of interest.
Statement on the welfare of animals
All applicable international, national, and/or institutional guidelines for the care and use of animals were followed.
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