title: Electrolytic lesions of the bilateral ventrolateral orbital cortex inhibit methamphetamine-associated contextual memory formation in rats.
abstract: The memories that are formed between rewarding and drug-associated contextual cues have been suggested to contribute to drug addiction relapse. Recent evidence has indicated that the ventrolateral orbital cortex (VLO) plays important roles in reward-based learning and reversal learning. However, whether the VLO is required for methamphetamine-induced contextual memory formation is not well understood. In the present study, a three-phase methamphetamine-induced conditioned place preference (CPP) model was used to investigate the effects of VLO lesions on the formation of drug-associated contextual memories in rats. We found that the VLO lesions themselves elicited no observable effects on place preferences. However, the VLO lesions delayed the acquisition and extinction phases of CPP without affecting the expression level. Furthermore, the VLO lesions did not have an obvious influence on CPP reinstatement. These results indicate that electrolytic lesions of the bilateral ventrolateral orbital cortex can inhibit the formation of methamphetamine-induced contextual memories in rats. Moreover, VLO may not be critically involved in memory storage and retrieval.
authors.affiliation: College of Medicine & Forensics, Xi׳an Jiaotong University Health Science Center, Xi׳an 710061, China; Institute of Basic Medicine Science, Xi׳an Medical University, Xi׳an 710021, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: College of Medicine & Forensics, Xi׳an Jiaotong University Health Science Center, Xi׳an 710061, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Liu
authors.affiliation: College of Medicine & Forensics, Xi׳an Jiaotong University Health Science Center, Xi׳an 710061, China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Chu
authors.affiliation: College of Medicine & Forensics, Xi׳an Jiaotong University Health Science Center, Xi׳an 710061, China; Affiliated Stomatology Hospital of Xi׳an Jiaotong University Health Science Center, Xi׳an 710004, Shaanxi, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Liu
authors.affiliation: College of Medicine & Forensics, Xi׳an Jiaotong University Health Science Center, Xi׳an 710061, China; Key Laboratory of the Health Ministry for Forensic Medicine, Xi׳an Jiaotong University Health Science Center, Xi׳an 710061, China; Key Laboratory of Environment and Genes Related to Diseases of the Education Ministry, Xi׳an Jiaotong University Health Science Center, Xi׳an 710061, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Han
authors.affiliation: College of Medicine & Forensics, Xi׳an Jiaotong University Health Science Center, Xi׳an 710061, China; Key Laboratory of the Health Ministry for Forensic Medicine, Xi׳an Jiaotong University Health Science Center, Xi׳an 710061, China; Key Laboratory of Environment and Genes Related to Diseases of the Education Ministry, Xi׳an Jiaotong University Health Science Center, Xi׳an 710061, China.
authors.forename: Xi
authors.initials: X
authors.lastname: Xun
authors.affiliation: College of Medicine & Forensics, Xi׳an Jiaotong University Health Science Center, Xi׳an 710061, China; Key Laboratory of the Health Ministry for Forensic Medicine, Xi׳an Jiaotong University Health Science Center, Xi׳an 710061, China; Key Laboratory of Environment and Genes Related to Diseases of the Education Ministry, Xi׳an Jiaotong University Health Science Center, Xi׳an 710061, China. Electronic address: psydyh@mail.xjtu.edu.cn.
authors.forename: Yong-Hui
authors.initials: YH
authors.lastname: Dang
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D000697:Central Nervous System Stimulants / Q000494:pharmacology*; D003216:Conditioning, Operant / Q000187:drug effects*; D004572:Electrolysis / Q000009:adverse effects; D005106:Exploratory Behavior / Q000187:drug effects; D005108:Extinction, Psychological / Q000187:drug effects; D008297:Male; D008568:Memory / Q000187:drug effects; D008694:Methamphetamine / Q000494:pharmacology*; D017397:Prefrontal Cortex / Q000293:injuries* / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012201:Reward; D013997:Time Factors
chemical_list: D000697:Central Nervous System Stimulants; D008694:Methamphetamine
keywords: Conditioned place preference; Memory; Methamphetamine; Ventrolateral orbital cortex