Journal of Molecular Neuroscience

, Volume 13, Issue 1–2, pp 69–75 | Cite as

Region-specific changes in prodynorphin mRNA and ir-dynorphin A levels after kindled seizures

  • P. Romualdi
  • G. Bregola
  • A. Donatini
  • A. Capobianco
  • M. Simonato
Article

Abstract

The opioid peptide dynorphin is thought to be implicated in specific types of seizures.In particular,complex partial seizures have been shown to cause release of dynorphin,activation of prodynorphin gene expression,and new peptide synthesis in the hippocampus.In this study, the kinetics of the seizure-induced changes in prodynorphin mRNA and ir-dynorphin Alevels in the hippocampus have been compared with those induced in the temporal and frontal cortex, i.e.,in other regions involved in the pathophysiology of complex partial seizures.Experiments have been run using kindling,one of the most valuable models of partial epilepsy.In the hippocampus (1)prodynorphin mRNA levels transiently increase (threefold)1 h after kindled seizures,and return to baseline by 2 h,and (2)dynorphin Alevels are slightly decreased at 1 h, but increase (twofold)at 2 h and return to baseline by 6 h.In the temporal and in the frontal cortex,a late (beginning at 2 h)and prolonged (up to 24 h)decrease in both prodynorphin mRNA and ir-dynorphin A levels have been observed.These data suggest that differential changes in dynorphin metabolism occur in different brain areas after seizures.The mechanisms and functional implications of this observation remain to be investigated.

Keywords

Frontal Cortex Temporal Lobe Epilepsy Molecular Neuroscience Volume Kainic Acid Complex Partial Seizure 

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Copyright information

© Humana Press Inc 1999

Authors and Affiliations

  • P. Romualdi
    • 1
  • G. Bregola
    • 2
  • A. Donatini
    • 1
  • A. Capobianco
    • 1
  • M. Simonato
    • 2
  1. 1.Department of PharmacologyUniversity of BolognaBologna
  2. 2.Department of Clinical and Experimental Medicine, Section of PharmacologyUniversity of FerraraFerraraItaly

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