Morphine modulates glutamate release in the hippocampal CA1 area in mice

Neurosci Lett. 2005 Jun 10-17;381(1-2):12-5. doi: 10.1016/j.neulet.2005.01.071. Epub 2005 Feb 16.


Opiate abuse is associated with long-lasting neural adaptative changes in the brain. Increasing evidence demonstrates that opiates significantly alter the function of the glutamatergic system, while how the system is regulated still remains elusive. In the present study, we studied the effect of morphine on extracellular glutamate concentration in the hippocampus, a nucleus rich of the glutamatergic neurons. The results showed that glutamate concentration in the extracellular fluid of the hippocampus was decreased following either acute or chronic treatment of morphine. However, naloxone-induced withdrawal increased glutamate concentration significantly. These results suggest an adaptation of the glutamatergic neuronal transmission in the hippocampus after morphine treatment.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptation, Physiological / drug effects
  • Animals
  • Dose-Response Relationship, Drug
  • Glutamic Acid / metabolism*
  • Hippocampus / drug effects
  • Hippocampus / metabolism*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Morphine / administration & dosage*
  • Morphine Dependence / metabolism*
  • Substance Withdrawal Syndrome / metabolism*
  • Synaptic Transmission / drug effects*


  • Glutamic Acid
  • Morphine