TY - JOUR
T1 - Blockade of the K ATP channel Kir6.2 by memantine represents a novel mechanism relevant to Alzheimer's disease therapy
AU - Moriguchi, S.
AU - Ishizuka, Toru
AU - Yabuki, Yasushi
AU - Shioda, Norifumi
AU - Sasaki, Y.
AU - Tagashira, H.
AU - Yawo, Hiromu
AU - Yeh, J. Z.
AU - Sakagami, H.
AU - Narahashi, T.
AU - Fukunaga, Koji
N1 - Funding Information:
This work was supported in part by grants from the Ministry of Education, Culture, Sports, Science and Technology, and the Ministry of Health and Welfare of Japan (22390109 to KF; 20790398 to SM). Also, thanks to Professor Tsuyoshi Miyakawa for providing CaMKIIα +/ − mice and Professor Susumu Seino for providing Kir6.1 +/ − and Kir6.2 − / − mice. We also thank Novartis Pharma for providing APP23 mice.
Funding Information:
This work was supported in part by grants from the Ministry of Education, Culture, Sports, Science and Technology, and the Ministry of Health and Welfare of Japan (22390109 to KF; 20790398 to SM). Also, thanks to Professor Tsuyoshi Miyakawa for providing CaMKIIα +/-mice and Professor Susumu Seino for providing Kir6.1 +/-and Kir6.2-/-mice. We also thank Novartis Pharma for providing APP23 mice.
Publisher Copyright:
© 2018 Macmillan Publishers Limited, part of Springer Nature. All rights reserved.
PY - 2018/2/1
Y1 - 2018/2/1
N2 - Here, we report a novel target of the drug memantine, ATP-sensitive K + (K ATP ) channels, potentially relevant to memory improvement. We confirmed that memantine antagonizes memory impairment in Alzheimer's model APP23 mice. Memantine increased CaMKII activity in the APP23 mouse hippocampus, and memantine-induced enhancement of hippocampal long-term potentiation (LTP) and CaMKII activity was totally abolished by treatment with pinacidil, a specific opener of K ATP channels. Memantine also inhibited Kir6.1 and Kir6.2 K ATP channels and elevated intracellular Ca 2+ concentrations in neuro2A cells overexpressing Kir6.1 or Kir6.2. Kir6.2 was preferentially expressed at postsynaptic regions of hippocampal neurons, whereas Kir6.1 was predominant in dendrites and cell bodies of pyramidal neurons. Finally, we confirmed that Kir6.2 mutant mice exhibit severe memory deficits and impaired hippocampal LTP, impairments that cannot be rescued by memantine administration. Altogether, our studies show that memantine modulates Kir6.2 activity, and that the Kir6.2 channel is a novel target for therapeutics to improve memory impairment in Alzheimer disease patients.
AB - Here, we report a novel target of the drug memantine, ATP-sensitive K + (K ATP ) channels, potentially relevant to memory improvement. We confirmed that memantine antagonizes memory impairment in Alzheimer's model APP23 mice. Memantine increased CaMKII activity in the APP23 mouse hippocampus, and memantine-induced enhancement of hippocampal long-term potentiation (LTP) and CaMKII activity was totally abolished by treatment with pinacidil, a specific opener of K ATP channels. Memantine also inhibited Kir6.1 and Kir6.2 K ATP channels and elevated intracellular Ca 2+ concentrations in neuro2A cells overexpressing Kir6.1 or Kir6.2. Kir6.2 was preferentially expressed at postsynaptic regions of hippocampal neurons, whereas Kir6.1 was predominant in dendrites and cell bodies of pyramidal neurons. Finally, we confirmed that Kir6.2 mutant mice exhibit severe memory deficits and impaired hippocampal LTP, impairments that cannot be rescued by memantine administration. Altogether, our studies show that memantine modulates Kir6.2 activity, and that the Kir6.2 channel is a novel target for therapeutics to improve memory impairment in Alzheimer disease patients.
UR - http://www.scopus.com/inward/record.url?scp=84992390024&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84992390024&partnerID=8YFLogxK
U2 - 10.1038/mp.2016.187
DO - 10.1038/mp.2016.187
M3 - Article
C2 - 27777420
AN - SCOPUS:84992390024
SN - 1359-4184
VL - 23
SP - 211
EP - 221
JO - Molecular Psychiatry
JF - Molecular Psychiatry
IS - 2
ER -
