NEUROCHEMISTRYUnlike lithium, anticonvulsants and antidepressants do not alter rat brain myo-inositolMcGrath, Brent M.a; Greenshaw, Andrew J.a; McKay, Ryanb; Slupsky, Carolyn M.c; Silverstone, Peter H.aAuthor Information aDepartment of Psychiatry bNational High Field Magnetic Resonance Centre cMetabolomics Centre, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada Correspondence to Brent M. McGrath, BSc, MSc, PhD, Faculty of Medicine, Dalhousie University, Sir Charles Tupper Medical Building, 5849 University Avenue, PO Box 265, Halifax, NS, Canada, B3H 4H7 Tel: +902 401 9409; e-mail: firstname.lastname@example.org Received 12 June 2007; accepted 13 July 2007 NeuroReport: October 8th, 2007 - Volume 18 - Issue 15 - p 1595-1598 doi: 10.1097/WNR.0b013e3282f03f09 Buy Metrics Abstract Lithium is the first-line in bipolar disorder treatment. Lithium's clinical efficacy might be due to its inhibition of myo-inositol turnover in the phosphatidylinositol second messenger system. This study aimed to determine whether this action can extend to antidepressants and anticonvulsants also used to treat bipolar symptoms. Male rats were treated for 2 weeks with an intraperitoneal injection of phenelzine, fluoxetine, desipramine, carbamazepine, lamotrigine, sodium valproate or vehicle. Brains were dissected and myo-inositol concentrations were analyzed using high-field nuclear magnetic resonance spectroscopy at 18.8 T and quantified using Chenomx Profiler software. Brain regions assessed included the prefrontal, temporal and occipital cortical areas as well as the hippocampus. The main finding is that contrary to lithium, the anticonvulsants and antidepressants do not alter brain myo-inositol concentration. This suggests that these agents might work via a mechanism that is not centered on changes in myo-inositol concentration. © 2007 Lippincott Williams & Wilkins, Inc.