title: Role of hippocampal CA1 area gap junction channels on morphine state-dependent learning.
abstract: Morphine produces a state dependent learning. The hippocampus is involved in this kind of learning. Gap junctions (GJs) are involved in some of the effects of morphine and exist in different areas of the hippocampus. We investigated the effects of blocking GJ channels of the hippocampal CA1 area, by means of pre-test bilateral injection of carbenoxolone (CBX), on morphine state dependent learning, using a passive avoidance task. Post-training subcutaneous administrations of morphine (0.5, 2.5, 5 and 7.5 mg/kg) dose-dependently impaired memory retrieval. Pre-test administration of morphine (0.5, 2.5, 5 and 7.5 mg/kg) induced a state-dependent retrieval of the memory acquired under post-training morphine influence. Pre-test injections of CBX (25, 75 and 150 nM) dose dependently prevented memory retrieval by post-training (7.5 mg/kg) and pre-test (0.5, 2.5, 5, 7.5 mg/kg) injections of morphine. The results suggest that intercellular coupling via GJ channels of the hippocampal CA1 area modulates morphine state dependent learning.
authors.affiliation: Division of Animal Sciences, Department of Biology, Faculty of Science, University of Isfahan, Isfahan, Iran. Electronic address: siamak.beheshti@yahoo.com.
authors.forename: Siamak
authors.initials: S
authors.lastname: Beheshti
authors.affiliation: Division of Animal Sciences, Department of Biology, Faculty of Science, University of Isfahan, Isfahan, Iran.
authors.forename: Seyyed Akbar Mir Seyyed
authors.initials: SA
authors.lastname: Hosseini
authors.affiliation: Division of Animal Sciences, Department of Biology, Faculty of Science, University of Isfahan, Isfahan, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Noorbakhshnia
authors.affiliation: Division of Animal Sciences, Department of Biology, Faculty of Science, University of Isfahan, Isfahan, Iran.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Eivani
mesh_terms: D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects / Q000502:physiology; D056547:CA1 Region, Hippocampal / Q000033:anatomy & histology / Q000187:drug effects* / Q000502:physiology*; D002229:Carbenoxolone / Q000008:administration & dosage / Q000494:pharmacology; D017629:Gap Junctions / Q000187:drug effects* / Q000502:physiology; D007858:Learning / Q000187:drug effects* / Q000502:physiology; D008297:Male; D008568:Memory / Q000187:drug effects / Q000502:physiology; D009020:Morphine / Q000008:administration & dosage / Q000494:pharmacology*; D009294:Narcotics / Q000008:administration & dosage / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar
chemical_list: D009294:Narcotics; D009020:Morphine; D002229:Carbenoxolone
keywords: Carbenoxolone; Carbenoxolone (PubChem CID: 13055197); Hippocampal CA(1) area; Ketamine Hydrochloride (PubChem CID:15851); Morphine; Morphine (PubChem CID: 5464280); State dependent learning; Xylazine Hydrochloride (PubChem CID: 68554)