title: Clozapine inhibits strychnine-sensitive glycine receptors in rat hippocampal neurons.
abstract: Seizure is one kind of severe side effects during clozapine (Clo) treatment. However, the mechanism of seizure associated with Clo therapy is not completely clear. Strychnine-sensitive glycine receptors (GlyRs) play an important role in regulating the excitability in the hippocampus. In the present study, we investigated the effect of Clo on GlyRs in cultured hippocampal neurons of rats. Clo reversibly inhibited the glycine-induced chloride currents (I(Gly)) in a concentration-dependent manner. The half-maximal effect concentration (EC(50)) for glycine alone was 25.6+/-0.7 microM with the Hill coefficient 1.5+/-0.1; in the presence of Clo, the EC(50) and the Hill coefficient were 28.9+/-6.3 microM and 1.2+/-0.3 respectively, which were not significantly affected by Clo. In addition, Clo inhibition of I(Gly) was not influenced by blocking D(1) and D(2) dopamine receptors with haloperidol (Hal). Taken together, these results suggest that Clo is a non-competitive antagonist of GlyR independent of its activation of dopamine receptors, which may contribute to seizure associated with Clo therapy.
authors.affiliation: Mental Health Institute, The Second Xiangya Hospital, Central South University, Changsha, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Liu
authors.forename: Changping
authors.initials: C
authors.lastname: Hu
authors.forename: Yamei
authors.initials: Y
authors.lastname: Tang
authors.forename: Jindong
authors.initials: J
authors.lastname: Chen
authors.forename: Min
authors.initials: M
authors.lastname: Dong
authors.forename: Tao
authors.initials: T
authors.lastname: Song
authors.forename: Xianghui
authors.initials: X
authors.lastname: Zhang
authors.forename: Jingping
authors.initials: J
authors.lastname: Zhao
mesh_terms: D000818:Animals; D014150:Antipsychotic Agents / Q000494:pharmacology*; D002478:Cells, Cultured; D003024:Clozapine / Q000494:pharmacology*; D006624:Hippocampus / Q000187:drug effects* / Q000378:metabolism; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D018408:Patch-Clamp Techniques; D051381:Rats; D017207:Rats, Sprague-Dawley; D018009:Receptors, Glycine / Q000187:drug effects* / Q000378:metabolism
chemical_list: D014150:Antipsychotic Agents; D018009:Receptors, Glycine; C027822:strychnine receptor; D003024:Clozapine