Antiepileptic Effects of 20-Hydroxyecdysone on Convulsive Seizures in Spontaneously Epileptic Rats
Ryosuke Hanaya (1), Masashi Sasa (2,*), Kumatoshi Ishihara (2), Tomohide
Akimitsu (1), Koji Iida (1), Taku Amano (2), Tadao Serikawa (3), Kazunori
Arita (1) and Kaoru Kurisu (1)
Departments of (1) Neurosurgery and (2) Pharmacology, Hiroshima University
School of Medicine, Hiroshima 734, Japan
(3) Institute of Laboratory Animals, Faculty of Medicine, Kyoto University,
Kyoto 606, Japan
(*) To whom correspondence should be addressed.
Abstract: We examined the effect of 20-hydroxyecdysone (20-HE),
a neurosteroid found in insects that is involved in their developmental
process, on both tonic convulsion and absence-like seizure in spontaneously
epileptic rat (SER). When 20-HE was given orally to SER at 25 - 200 mg/kg,
significant decreases of the tonic convulsion were observed with 100 and
200 mg/kg. Pretreatment of the animal with bicuculline (1 mg/kg, i.p.) antagonized
the inhibitory effects of 20-HE. However, absence-like seizures were not
affected by 20-HE. These findings indicate that 20-HE produces antiepileptic
effects on tonic convulsion by acting on the modulatory site of GABAA receptors.
Keywords: Spontaneously epileptic rat (SER), 20-Hydroxyecdysone, Antiepileptic
effect