title: Lack of effect of ketamine on cortical glutamate and glutamine in healthy volunteers: a proton magnetic resonance spectroscopy study.
abstract: Ketamine is a N-methyl-D-aspartic acid (NMDA) antagonist that has been associated with temporary clinical improvement in patients with depression. Studies using magnetic resonance spectroscopy (MRS) have shown that major depression is associated with decreased levels of glutamate and glutamine (Glx) in the anterior cingulate cortex, which normalize with clinical recovery. The present study aimed to test whether a ketamine infusion would increase cortical Glx levels in healthy volunteers. Healthy volunteers received an intravenous infusion of ketamine (0.5 mg kg⁻¹, n = 8) or saline (n = 9) over 40 minutes. MRS measurements were obtained at baseline, during, and at the end of the infusion. The infusion of ketamine had significant effects on mental state but there was no effect of ketamine on the levels of Glx (F (3,39) = 1.70, p = 0.18) or glutamate (F (3,39) = 48, p = 0.70). This study suggests that the gradual infusion of low-dose ketamine in antidepressant doses not cause changes in cortical glutamate or glutamine in healthy volunteers that are visible by proton MRS.
authors: Department of Psychiatry, University of Oxford, Oxford, UK. matthew.taylor@psych.ox.ac.uk
authors: Matthew J
authors: MJ
authors: Taylor
authors: Eleanor R
authors: ER
authors: Tiangga
authors: Roísín Ní
authors: RN
authors: Mhuircheartaigh
authors: Philip J
authors: PJ
authors: Cowen
references: Biol Psychiatry. 2005 Dec 15;58(12):969-73
references: 16043137
references: NMR Biomed. 2001 Jun;14(4):260-4
references: 11410943
references: IEEE Trans Med Imaging. 2001 Jan;20(1):45-57
references: 11293691
references: Am J Psychiatry. 2005 Feb;162(2):394-6
references: 15677610
references: Arch Gen Psychiatry. 2007 Feb;64(2):193-200
references: 17283286
references: J Neurosci. 1997 Apr 15;17(8):2921-7
references: 9092613
references: Biol Psychiatry. 2000 Feb 15;47(4):351-4
references: 10686270
references: Int J Neuropsychopharmacol. 2008 Mar;11(2):255-60
references: 17625025
references: J Neurosci. 2007 Oct 24;27(43):11496-500
references: 17959792
references: Magn Reson Med. 2004 Mar;51(3):435-40
references: 15004781
references: Arch Gen Psychiatry. 2006 Aug;63(8):856-64
references: 16894061
references: Magn Reson Med. 2006 Dec;56(6):1365-70
references: 17051529
references: Arch Gen Psychiatry. 2010 Aug;67(8):793-802
references: 20679587
references: Biol Psychiatry. 2000 Feb 15;47(4):305-13
references: 10686265
references: Schizophr Res. 2006 Feb 28;82(2-3):203-11
references: 16417985
references: J Magn Reson. 1997 Nov;129(1):35-43
references: 9405214
references: Schizophr Bull. 1991;17(4):555-64
references: 1805349
references: J Affect Disord. 2009 Dec;119(1-3):186-9
references: 19324421
references: Acta Radiol. 2010 Apr;51(3):309-15
references: 20170295
references: Arch Gen Psychiatry. 2006 Jun;63(6):611-21
references: 16754834
references: Arch Gen Psychiatry. 1994 Mar;51(3):199-214
references: 8122957