Regional metabolite levels and turnover in the awake rat brain under the influence of nicotine

J Neurochem. 2010 Jun;113(6):1447-58. doi: 10.1111/j.1471-4159.2010.06684.x. Epub 2010 Mar 14.

Abstract

As one of the most widespread drugs of abuse, nicotine has long been known to impact the brain, particularly with respect to addiction. However, the regional effects of nicotine on the concentrations and kinetics of amino acid neurotransmitters and some energetically related neurochemicals have been little studied. In this investigation, acute effects of nicotine were measured by (1)H-observed/(13)C-edited nuclear magnetic resonance spectroscopy method in extracts obtained from nicotine-naïve, freely moving rats given 0.7 mg/kg nicotine or saline, with [1-(13)C] glucose to track metabolism. Nicotine was observed to exert significant effects on the concentrations of N-acetylaspartate and GABA, particularly in the striatum. Nicotine decreased brain glucose oxidation, glutamate-glutamine neurotransmitter cycling, and GABA synthesis regionally, including in the parietal and occipital cortices and the striatum. The olfactory bulb showed kinetics that differed markedly from those observed in the rest of the brain. Independently of nicotine, the concentration of glutamate was found to be correlated significantly with levels of N-acetylaspartate and GABA, suggesting a potential interplay of energetics and excitatory and inhibitory neurotransmission. In summary, the study revealed that the neurochemicals were most affected in the cortex and striatum of the rat brain after acute nicotine treatment.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Amino Acids / metabolism
  • Animals
  • Aspartic Acid / analogs & derivatives
  • Aspartic Acid / metabolism
  • Brain / cytology
  • Brain / drug effects*
  • Brain / metabolism*
  • Isotopes / metabolism
  • Magnetic Resonance Spectroscopy / methods
  • Male
  • Models, Biological
  • Nicotine / pharmacology*
  • Nicotinic Agonists / pharmacology*
  • Plasma / drug effects
  • Plasma / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Time Factors
  • Wakefulness*

Substances

  • Amino Acids
  • Isotopes
  • Nicotinic Agonists
  • Aspartic Acid
  • Nicotine
  • N-acetylaspartate