title: Role of glutamate transporters in the modulation of stress-induced lactate metabolism in the rat brain.
abstract: BACKGROUND
  Lactate, like glucose, has recently been found to be an energy substrate for neural activity. It is indicated that lactate is produced by astrocytes under the regulation of glutamatergic tone.
  
  
  OBJECTIVE
  Using in vivo microdialysis technique, we measured extracellular lactate concentrations in the medial prefrontal cortex (mPFC) and basolateral amygdala (BLA) of rats. To investigate the role of the glutamate transporter in the modulation of footshock stress-induced energy demands in both brain regions, we attempted to determine whether the footshock stress-induced changes of extracellular lactate concentrations are attenuated by local perfusion of the glutamate uptake inhibitor dihydrokainate (DHK).
  
  
  RESULTS
  Perfusion of 1.0 mM DHK produced an increase in basal extracellular lactate levels in the mPFC and BLA, whereas 0.1 mM DHK did not affect lactate concentrations in either region. DHK also attenuated stress-induced increment of extracellular lactate concentrations in the mPFC, and completely prevented it in the BLA.
  
  
  CONCLUSIONS
  These results suggest that glutamate transporters regulate lactate availability in astrocytes and indicate that the rapid energy demand induced by glutamate contributes to local lactate production.
authors: Department of Neuropsychiatry, University of Toyama Graduate School of Medicine and Pharmaceutical Science, 2630 Sugitani, Toyama 930-0194, Japan. uehara@med.u-toyama.ac.jp
authors: Takashi
authors: T
authors: Uehara
authors: Tomiki
authors: T
authors: Sumiyoshi
authors: Hiroko
authors: H
authors: Itoh
authors: Masayoshi
authors: M
authors: Kurachi
mesh_terms: D000679:Amygdala / Q000378:metabolism; D000704:Analysis of Variance; D000818:Animals; D001921:Brain / Q000378:metabolism*; D004734:Energy Metabolism; D027342:Excitatory Amino Acid Transporter 2 / Q000037:antagonists & inhibitors / Q000502:physiology*; D007608:Kainic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D019344:Lactic Acid / Q000378:metabolism*; D008297:Male; D017551:Microdialysis; D014179:Neurotransmitter Uptake Inhibitors / Q000494:pharmacology*; D017397:Prefrontal Cortex / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013315:Stress, Psychological / Q000378:metabolism*
chemical_list: D027342:Excitatory Amino Acid Transporter 2; D014179:Neurotransmitter Uptake Inhibitors; D019344:Lactic Acid; C020889:dihydrokainic acid; D007608:Kainic Acid
references: J Cereb Blood Flow Metab. 2003 Nov;23(11):1263-81
references: 14600433
references: J Neurochem. 1979 Jan;32(1):121-7
references: 759563
references: Proc Natl Acad Sci U S A. 1994 Oct 25;91(22):10625-9
references: 7938003
references: Am J Physiol. 1992 Sep;263(3 Pt 2):R722-7
references: 1415663
references: Psychopharmacology (Berl). 2006 Jun;186(2):218-25
references: 16596399
references: Proc Natl Acad Sci U S A. 1998 Jan 6;95(1):316-21
references: 9419373
references: Dev Neurosci. 1998;20(4-5):291-9
references: 9778565
references: J Physiol. 1997 Mar 15;499 ( Pt 3):825-32
references: 9130175
references: Eur J Neurosci. 2000 Nov;12(11):3843-53
references: 11069579
references: Brain Res. 2007 Feb 16;1133(1):193-9
references: 17184754
references: J Pharmacol Exp Ther. 1999 Jun;289(3):1600-10
references: 10336558
references: J Cereb Blood Flow Metab. 1988 Dec;8(6):848-56
references: 3192650
references: Eur J Pharmacol. 2003 Jan 17;459(2-3):211-5
references: 12524148
references: Brain Res. 1988 Dec 13;475(1):58-63
references: 2850837
references: J Neurosci. 1996 Feb 1;16(3):877-85
references: 8558256
references: Science. 1999 Jan 22;283(5401):496-7
references: 9988650
references: J Neurochem. 1997 Nov;69(5):2132-7
references: 9349559
references: Glia. 2005 Jan 1;49(1):134-42
references: 15390097
references: Neurosci Lett. 2007 Mar 30;415(3):259-63
references: 17280781
references: Neuron. 1994 Sep;13(3):713-25
references: 7917301
references: J Neurosci. 1995 Mar;15(3 Pt 1):1835-53
references: 7891138
references: J Neurochem. 2000 Oct;75(4):1634-44
references: 10987845
references: Brain Res. 2003 Oct 31;989(1):112-6
references: 14519517
references: J Neurosci. 1994 Sep;14(9):5559-69
references: 7521911
references: Brain Res. 2005 Dec 14;1065(1-2):86-91
references: 16309628
references: Neurochem Int. 2003 Sep-Oct;43(4-5):331-8
references: 12742077
references: Proc Natl Acad Sci U S A. 1991 Jul 1;88(13):5829-31
references: 2062861
references: Neurochem Int. 1998 Dec;33(6):479-91
references: 10098717