title: Effects of rhynchophylline on GluN1 and GluN2B expressions in primary cultured hippocampal neurons.
abstract: N-methyl-d-aspartate (NMDA) receptor subunits GluN1 and GluN2B in hippocampal neurons play key roles in anxiety. Our previous studies show that rhynchophylline, an active component of the Uncaria species, down-regulates GluN2B expression in the hippocampal CA1 area of amphetamine-induced rat. The effects of rhynchophylline on expressions of GluN1 and GluN2B in primary hippocampal neurons in neonatal rats in vitro were investigated. Neonatal hippocampal neurons were cultured with neurobasal-A medium. After incubation for 6h or 48 h with rhynchophylline (non-competitive NMDAR antagonist) and MK-801 (non-competitive NMDAR antagonist with anxiolytic effect, as the control drug) from day 6, neuron toxicity, mRNA and protein expressions of GluN1 and GluN2B were analyzed. GluN1 is mainly distributed on neuronal axons and dendritic trunks, cytoplasm and cell membrane near axons and dendrites. GluN2B is mainly distributed on the membrane, dendrites, and axon membranes. GluN1 and GluN2B are codistributed on dendritic trunks and dendritic spines. After 48 h incubation, a lower concentration of rhynchophylline (lower than 400 μmol/L) and MK-801 (lower than 200 μmol/L) have no toxicity on neonatal hippocampal neurons. Rhynchophylline up-regulated GluN1 mRNA expression at 6h and mRNA and protein expressions at 48h, but down-regulated GluN2B mRNA and protein expressions at 48 h. However, GluN1 and GluN2B mRNA expressions were down-regulated at 6h, and mRNA and protein expressions were both up-regulated by MK-801 at 48h. These findings show that rhynchophylline reciprocally regulates GluN1 and GluN2B expressions in hippocampal neurons, indicating a potential anxiolytic property for rhynchophylline.
authors.affiliation: National Drug Clinical Trial Institution, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, PR China; College of Traditional Chinese Medicine, Southern Medical University, Guangdong, Guangzhou 510515, PR China.
authors.forename: Yan
authors.initials: Y
authors.lastname: He
authors.affiliation: National Drug Clinical Trial Institution, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, PR China.
authors.forename: Sheng-Ya
authors.initials: SY
authors.lastname: Zeng
authors.affiliation: National Drug Clinical Trial Institution, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, PR China.
authors.forename: Shi-Wen
authors.initials: SW
authors.lastname: Zhou
authors.affiliation: Institute of Respiratory Diseases, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, PR China.
authors.forename: Gui-Sheng
authors.initials: GS
authors.lastname: Qian
authors.affiliation: College of Traditional Chinese Medicine, Southern Medical University, Guangdong, Guangzhou 510515, PR China.
authors.forename: Kang
authors.initials: K
authors.lastname: Peng
authors.affiliation: College of Traditional Chinese Medicine, Southern Medical University, Guangdong, Guangzhou 510515, PR China.
authors.forename: Zhi-Xian
authors.initials: ZX
authors.lastname: Mo
authors.affiliation: National Drug Clinical Trial Institution, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, PR China. Electronic address: zhoujiyin@gmail.com.
authors.forename: Ji-Yin
authors.initials: JY
authors.lastname: Zhou
mesh_terms: D000818:Animals; D001369:Axons / Q000187:drug effects; D002478:Cells, Cultured; D003712:Dendrites / Q000187:drug effects; D016291:Dizocilpine Maleate / Q000494:pharmacology; D006624:Hippocampus / Q000166:cytology*; D026121:Indole Alkaloids / Q000494:pharmacology*; D009474:Neurons / Q000187:drug effects*; D000078183:Oxindoles; D061251:Primary Cell Culture; D051381:Rats; D017207:Rats, Sprague-Dawley; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors / Q000378:metabolism*; D032070:Uncaria / Q000737:chemistry
chemical_list: D026121:Indole Alkaloids; C121001:NR2B NMDA receptor; D000078183:Oxindoles; D016194:Receptors, N-Methyl-D-Aspartate; C052714:rhyncophylline; D016291:Dizocilpine Maleate
keywords: GluN2B; Hippocampal neurons; NMDA receptor subunit GluN1; Neonatal rats; Rhynchophylline; Toxicity