BACKGROUND: Recent evidence suggests that effects upon glutamatergic transmission may contribute to the therapeutic action of certain atypical antipsychotic agents. METHODS: Glutamate concentrations were measured in serum and were estimated (Glx/Cr) in cingulate cortex by proton magnetic resonance spectroscopy (MRS) in schizophrenia patients while they were being treated with conventional neuroleptics and then 8 weeks after switching to olanzapine. Serum glutamate concentrations were obtained from 11 subjects, and MRS estimates of Glx/Cr were available from 10 subjects at both time points. RESULTS: Serum glutamate concentrations significantly increased after the switch from conventional agents to olanzapine; brain glutamate (Glx/Cr) did not change significantly; however, brain glutamate (Glx/Cr) concentrations increased significantly in patients who exhibited an improvement in negative symptoms with olanzapine compared with patients with no change or worsening of negative symptoms. CONCLUSIONS: Comparisons performed following the switch from conventional agents to olanzapine are consistent with previous studies of clozapine and provide additional preliminary evidence supporting the hypothesis that effects on excitatory amino acid activity may contribute to olanzapine's efficacy for treating negative symptoms.
BACKGROUND: Recent evidence suggests that effects upon glutamatergic transmission may contribute to the therapeutic action of certain atypical antipsychotic agents. METHODS:Glutamate concentrations were measured in serum and were estimated (Glx/Cr) in cingulate cortex by proton magnetic resonance spectroscopy (MRS) in schizophreniapatients while they were being treated with conventional neuroleptics and then 8 weeks after switching to olanzapine. Serum glutamate concentrations were obtained from 11 subjects, and MRS estimates of Glx/Cr were available from 10 subjects at both time points. RESULTS: Serum glutamate concentrations significantly increased after the switch from conventional agents to olanzapine; brain glutamate (Glx/Cr) did not change significantly; however, brain glutamate (Glx/Cr) concentrations increased significantly in patients who exhibited an improvement in negative symptoms with olanzapine compared with patients with no change or worsening of negative symptoms. CONCLUSIONS: Comparisons performed following the switch from conventional agents to olanzapine are consistent with previous studies of clozapine and provide additional preliminary evidence supporting the hypothesis that effects on excitatory amino acid activity may contribute to olanzapine's efficacy for treating negative symptoms.
Authors: Andreas Heinz; Dieter F Braus; Berenice Romero; Jürgen Gallinat; Imke Puls; Georg Juckel; Daniel R Weinberger Journal: Nervenarzt Date: 2004-09 Impact factor: 1.214
Authors: Jeffrey A Lieberman; Frank P Bymaster; Herbert Y Meltzer; Ariel Y Deutch; Gary E Duncan; Christine E Marx; June R Aprille; Donard S Dwyer; Xin-Min Li; Sahebarao P Mahadik; Ronald S Duman; Joseph H Porter; Josephine S Modica-Napolitano; Samuel S Newton; John G Csernansky Journal: Pharmacol Rev Date: 2008-09 Impact factor: 25.468
Authors: Eline M P Poels; Lawrence S Kegeles; Joshua T Kantrowitz; Daniel C Javitt; Jeffrey A Lieberman; Anissa Abi-Dargham; Ragy R Girgis Journal: Schizophr Res Date: 2014-01-11 Impact factor: 4.939
Authors: Donald C Goff; Corinne Cather; Jennifer D Gottlieb; A Eden Evins; Jared Walsh; Lisa Raeke; Michael W Otto; David Schoenfeld; Michael F Green Journal: Schizophr Res Date: 2008-09-16 Impact factor: 4.939