Abstract
Senktide, a potent neurokinin-3 receptor (NK3-R) agonist, has been shown to have promnestic effects in adult and aged rodents and to facilitate episodic-like memory (ELM) in mice when administrated before the learning trial. In the present study we assessed the effects of senktide on memory consolidation by administering it post-trial (after the learning trial) in adult rats. We applied an ELM test, based on the integrated memory for object, place and temporal order, which we developed (Kart-Teke, de Souza Silva, Huston, & Dere, 2006). This test involves two learning trials and one test trial. We examined intervals of 1. h and 23. h between the learning and test trials (experiment 1) in untreated animals and found that they exhibited intact ELM after a delay of 1. h, but not 23. h. In another test for ELM performed 7. days later, vehicle or senktide (0.2. mg/kg, s.c.) was applied immediately after the second learning trial and the test was conducted 23. h later (experiment 2). Senktide treatment recovered components of ELM (memory for place and object) compared with vehicle-treated animals. After one more week, vehicle or senktide (0.2. mg/kg, s.c.) was applied post-trial and the test conducted 6. h later (experiment 3). The senktide-treated group exhibited intact ELM, unlike the vehicle-treated group. Finally, animals received post-trial treatment with either vehicle or SR142801, a selective NK3-R antagonist (6. mg/kg, i.p.), 1. min before senktide injection (0.2. mg/kg, s.c.) in the ELM paradigm and were tested 6. h later (experiment 4). The vehicle. +. senktide group showed intact ELM, while the SR142801. +. senktide group did not. The results indicate that senktide facilitated the consolidation or the expression of ELM and that the senktide effect was NK3-R dependent.
Original language | English (US) |
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Pages (from-to) | 178-185 |
Number of pages | 8 |
Journal | Neurobiology of Learning and Memory |
Volume | 114 |
DOIs | |
State | Published - Oct 2014 |
Externally published | Yes |
Bibliographical note
Funding Information:This study was supported by a Grant from the Deutsche Forschungsgemeischaft SO1032/2-5 . M.A. de Souza Silva is recipient of a Heisenberg Fellowship given by the Deutsche Forschungsgemeischaft SO 1032/5-1.
Keywords
- Episodic-like memory
- NK3 receptors
- Object recognition
- Senktide