title: Optogenetic stimulation of mPFC pyramidal neurons as a conditioned stimulus supports associative learning in rats.
abstract: It is generally accepted that the associative learning occurs when a behaviorally neutral conditioned stimulus (CS) is paired with an aversive unconditioned stimulus (US) in close temporal proximity. Eyeblink conditioning (EBC) is a simple form of associative learning for motor responses. Specific activation of a population of cells may be an effective and sufficient CS for establishing EBC. However, there has been no direct evidence to support this hypothesis. Here, we show in rats that optogenetic activation of the right caudal mPFC pyramidal neurons as a CS is sufficient to support the acquisition of delay eyeblink conditioning (DEC). Interestingly, the associative memory was not stably expressed during the initial period of daily conditioning session even after the CR acquisition reached the asymptotic level. Finally, the intensity and consistency of the CS were found to be crucial factors in regulating the retrieval of the associative memory. These results may be of importance in understanding the neural cellular mechanisms underlying associative learning and the mechanisms underlying retrieval process of memory.
authors.affiliation: 1] Department of Physiology, College of Basic Medical Sciences, Third Military Medical University, Chongqing 400038, China [2] Experimental Center of Basic Medicine, College of Basic Medical Sciences, Third Military Medical University, Chongqing 400038, China.
authors.forename: Guang-yan
authors.initials: GY
authors.lastname: Wu
authors.affiliation: 1] Experimental Center of Basic Medicine, College of Basic Medical Sciences, Third Military Medical University, Chongqing 400038, China [2] Department of Neurosurgery, Southwest Hospital, Third Military Medical University, Chongqing 400038, China.
authors.forename: Guo-long
authors.initials: GL
authors.lastname: Liu
authors.affiliation: Department of Physiology, College of Basic Medical Sciences, Third Military Medical University, Chongqing 400038, China.
authors.forename: Hui-min
authors.initials: HM
authors.lastname: Zhang
authors.affiliation: Experimental Center of Basic Medicine, College of Basic Medical Sciences, Third Military Medical University, Chongqing 400038, China.
authors.forename: Chong
authors.initials: C
authors.lastname: Chen
authors.affiliation: Department of Physiology, College of Basic Medical Sciences, Third Military Medical University, Chongqing 400038, China.
authors.forename: Shu-lei
authors.initials: SL
authors.lastname: Liu
authors.affiliation: Department of Neurosurgery, Southwest Hospital, Third Military Medical University, Chongqing 400038, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Feng
authors.affiliation: 1] Department of Physiology, College of Basic Medical Sciences, Third Military Medical University, Chongqing 400038, China [2] Department of Neurosurgery, Southwest Hospital, Third Military Medical University, Chongqing 400038, China.
authors.forename: Jian-feng
authors.initials: JF
authors.lastname: Sui
mesh_terms: D000818:Animals; D001245:Association Learning / Q000502:physiology*; D001767:Blinking; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2 / Q000235:genetics / Q000378:metabolism; D000075402:Channelrhodopsins; D003214:Conditioning, Classical / Q000502:physiology*; D008297:Male; D008568:Memory / Q000502:physiology; D062308:Optogenetics / Q000379:methods; D017966:Pyramidal Cells / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D000075402:Channelrhodopsins; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2