Chronic low-dose maternal exposure to methylmercury enhances epileptogenicity in developing rats

A. Szász, B. Barna, Z. Szupera, G. De Visscher, Z. Galbács, M. Kirsch-Volders, M. Szente

Research output: Contribution to journalArticle

19 Citations (Scopus)

Abstract

Effects of continuous low-dose maternal methylmercury intoxication on the induction and propagation of ictal epileptiform activity induced by 3-aminopyridine, were investigated on the neocortex of 4-weeks-old offspring rats. Epileptogenicity was significantly increased in offspring of mercury-treated animals compared to those of controls, characterized by more frequent occurrence of periodic ictal activity, a facilitated propagation of epileptiform discharges and a strong tendency to generalization. The latency of first ictal event was slightly shorter and the average duration of individual ictal periods slightly longer in treated animals. However, the amplitude of seizure discharges was significantly smaller in treated animals than in controls.We conclude, that the synaptic and membrane mechanisms responsible for initiation and propagation of paroxysmal activity were probably facilitated, while the efficacy of cortical inhibition, in preventing initiation and spread of epileptiform discharges was reduced by mercury treatment in the developing nervous system. The smaller amplitude of paroxysmal discharges could be a sign of a remarkable loss of cortical neurons. Copyright (C) 1999 ISDN.

Original languageEnglish
Pages (from-to)733-742
Number of pages10
JournalInternational Journal of Developmental Neuroscience
Volume17
Issue number7
DOIs
Publication statusPublished - Nov 1999

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Maternal Exposure
Stroke
Mercury
Synaptic Membranes
Neocortex
Nervous System
Seizures
Mothers
Neurons

Keywords

  • Aminopyridine-induced epilepsy
  • Developmental exposure
  • Epileptogenicity
  • Methylmercury
  • Rat

ASJC Scopus subject areas

  • Developmental Biology
  • Developmental Neuroscience

Cite this

Chronic low-dose maternal exposure to methylmercury enhances epileptogenicity in developing rats. / Szász, A.; Barna, B.; Szupera, Z.; De Visscher, G.; Galbács, Z.; Kirsch-Volders, M.; Szente, M.

In: International Journal of Developmental Neuroscience, Vol. 17, No. 7, 11.1999, p. 733-742.

Research output: Contribution to journalArticle

Szász, A. ; Barna, B. ; Szupera, Z. ; De Visscher, G. ; Galbács, Z. ; Kirsch-Volders, M. ; Szente, M. / Chronic low-dose maternal exposure to methylmercury enhances epileptogenicity in developing rats. In: International Journal of Developmental Neuroscience. 1999 ; Vol. 17, No. 7. pp. 733-742.
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