Magnesium deficiency induces an hyperalgesia reversed by the NMDA receptor antagonist MK801

Neuroreport. 1997 Apr 14;8(6):1383-6. doi: 10.1097/00001756-199704140-00013.

Abstract

The aim of this study was to determine the changes of the nociceptive thresholds in response to an acute mechanical stimulus (paw pressure) in magnesium (Mg)-deficient rats, and the involvement of the NMDA receptor in these changes. Changes in vocalization thresholds was determined after 7 days of feeding with a Mg-depleted diet. Compared with the control group, Mg-deficient rats showed a significant decrease in the vocalization thresholds (-35.8 +/- 2.5%, p < 0.001) reflecting hyperalgesia. In Mg-deprived rats, three doses (0.06, 0.12 and 0.24 mg/kg s.c.) of dizocilpine (MK801), a non-competitive NMDA receptor antagonist, significantly reversed the hyperalgesia in a dose-dependent manner for at least 48 h. No effect of MK801 was observed in the control group. These data provide evidence that Mg deficiency could constitute a new model of hyperalgesia involving NMDA receptors.

MeSH terms

  • Analysis of Variance
  • Animals
  • Dizocilpine Maleate / pharmacology*
  • Dose-Response Relationship, Drug
  • Excitatory Amino Acid Antagonists / pharmacology*
  • Hyperalgesia / drug therapy*
  • Hyperalgesia / etiology
  • Hyperalgesia / physiopathology
  • Magnesium Deficiency / physiopathology*
  • Male
  • Pain Threshold / drug effects*
  • Rats
  • Rats, Wistar
  • Receptors, N-Methyl-D-Aspartate / antagonists & inhibitors*
  • Stress, Mechanical

Substances

  • Excitatory Amino Acid Antagonists
  • Receptors, N-Methyl-D-Aspartate
  • Dizocilpine Maleate