Neurochemical Research

, Volume 17, Issue 8, pp 779–783

Effects of morphine andd-Ala2-d-Leu5-enkephalin in the seizure-susceptible El mouse

  • Seiji Koide
  • Hiroshi Onishi
  • Sakae Yamagami
  • Yukio Kawakita
Original Articles


Opioid agonists were used to investigate the modulation of seizures in the seizure-susceptible El mouse. Morphine andd-Ala2-d-Leu5-enkephalin (DADLE) were injected subcutaneously or intracisternally as prototypic agonists for μ and δ opioid receptors. Systemic or intracisternal injection of both morphine and DADLE decreased the incidence of seizures and the seizure score in El mice in a dose-dependent manner. The anticonvulsant effects of morphine and DADLE were reversed by naloxone (2 mg/kg, s.c.). This implies that opioid agonists have anticonvulsant properties which are mediated by μ and δ opioid receptors. In conclusion, a deficit in endogenous opioid peptides, which act as anticonvulsants may play a significant role in the etiology or pathophysiology of seizures in the El mouse.

Key Words

El mouse morphine enkephalins seizure epilepsy 


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Copyright information

© Plenum Publishing Corporation 1992

Authors and Affiliations

  • Seiji Koide
    • 1
  • Hiroshi Onishi
    • 1
  • Sakae Yamagami
    • 1
  • Yukio Kawakita
    • 1
  1. 1.Department of NeuropsychiatryOsaka City University Medical SchoolOsakaJapan

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