| First Author | Karunakaran S | Year | 2021 |
| Journal | Sci Rep | Volume | 11 |
| Issue | 1 | Pages | 870 |
| PubMed ID | 33441593 | Mgi Jnum | J:300681 |
| Mgi Id | MGI:6502283 | Doi | 10.1038/s41598-020-79487-5 |
| Citation | Karunakaran S (2021) Early beta adrenoceptor dependent time window for fear memory persistence in APPswe/PS1dE9 mice. Sci Rep 11(1):870 |
| abstractText | In this study we demonstrate that 2 month old APPswe/PS1dE9 mice, a transgenic model of Alzheimer's disease, exhibited intact short-term memory in Pavlovian hippocampal-dependent contextual fear learning task. However, their long-term memory was impaired. Intra-CA1 infusion of isoproterenol hydrochloride, the beta-adrenoceptor agonist, to the ventral hippocampus of APPswe/PS1dE9 mice immediately before fear conditioning restored long-term contextual fear memory. Infusion of the beta-adrenoceptor agonist + 2.5 h after fear conditioning only partially rescued the fear memory, whereas infusion at + 12 h post conditioning did not interfere with long-term memory persistence in this mouse model. Furthermore, Intra-CA1 infusion of propranolol, the beta-adrenoceptor antagonist, administered immediately before conditioning to their wildtype counterpart impaired long-term fear memory, while it was ineffective when administered + 4 h and + 12 h post conditioning. Our results indicate that, long-term fear memory persistence is determined by a unique beta-adrenoceptor sensitive time window between 0 and + 2.5 h upon learning acquisition, in the ventral hippocampal CA1 of APPswe/PS1dE9 mice. On the contrary, beta-adrenoceptor agonist delivery to ventral hippocampal CA1 per se did not enhance innate anxiety behaviour in open field test. Thus we conclude that, activation of learning dependent early beta-adrenoceptor modulation underlies and is necessary to promote long-term fear memory persistence in APPswe/PS1dE9. |
