Nifedipine has paradoxical effects on the development of kindling but not on kindled seizures in amygdala-kindled rats

Norihito Yamada, D. K. Bilkey

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

The effects of nifedipine, an antagonist of voltage-operated calcium channels, on the development of amygdala kindling and on the production of fully kindled seizures, stimulated from the amygdala, were investigated. Rats were treated daily with two doses (5 and 50 mg/kg, i.p.) of nifedipine during the development of kindling. Both doses of nifedipine retarded the development of kindled seizures and 50 mg/kg of nifedipine prolonged the latency to the occurrence of bilateral forelimb clonus. In contrast to these antiepileptogenic effects, however, both doses also increased the duration of afterdischarge. This resulted in a striking increase in the cumulative duration of afterdischarge, required to reach stage 4 and 5 seizures. Contrary to the results of a previous study, 50 mg/kg of nifedipine did not produce any significant effect on fully kindled seizures, regardless of the interval (5 min-24 hr) between injection and stimulation of kindling. These results suggested that although nifedipine inhibited the propagation processes of seizures during development of kindling, it appeared to increase the duration of epileptic activity at the kindling focus.

Original languageEnglish
Pages (from-to)501-505
Number of pages5
JournalNeuropharmacology
Volume30
Issue number5
DOIs
Publication statusPublished - 1991
Externally publishedYes

Fingerprint

Nifedipine
Amygdala
Seizures
Forelimb
Calcium Channels
Injections

Keywords

  • amygdala kindling
  • amygdala-kindled seizure
  • epilepsy
  • nifedipine
  • rat
  • voltage-operated Ca channel antagonist

ASJC Scopus subject areas

  • Cellular and Molecular Neuroscience
  • Drug Discovery
  • Pharmacology

Cite this

Nifedipine has paradoxical effects on the development of kindling but not on kindled seizures in amygdala-kindled rats. / Yamada, Norihito; Bilkey, D. K.

In: Neuropharmacology, Vol. 30, No. 5, 1991, p. 501-505.

Research output: Contribution to journalArticle

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