Biphasic action of the histamine precursor L-histidine in the rat kindling model of epilepsy.
The effects of the histamine precursor, L-histidine, were examined in the rat kindling model of epilepsy. The intraperitoneal (i.p.) administration of 800 mg/kg L-histidine significantly prolonged the latency to the onset of bilateral forelimb clonus of previously kindled seizures from the amygdala (AM), with no significant effect observed in the behavioral seizure stage or afterdischarge duration. In contrast, daily administration of L-histidine at the same dose prior to each electrical stimulation to the AM significantly facilitated both behavioral and electrographic seizure development of kindling. The present results indicate that although L-histidine can suppress secondary generalization of AM-kindled seizures, it possesses a facilitatory effect on the acquisition of kindling epileptogenesis, suggesting a biphasic action of histamine in kindling.
Wada
Y
Y
Department of Neuropsychiatry, Kanazawa University School of Medicine, Japan.
Shiraishi
J
J
Nakamura
M
M
Koshino
Y
Y
D000679:Amygdala / Q000187:drug effects / Q000502:physiology; D000818:Animals; D004195:Disease Models, Animal; D004558:Electric Stimulation; D004827:Epilepsy / Q000188:drug therapy / Q000378:metabolism* / Q000503:physiopathology; D006632:Histamine / Q000096:biosynthesis* / Q000502:physiology; D006639:Histidine / Q000378:metabolism / Q000494:pharmacology*; D007696:Kindling, Neurologic / Q000187:drug effects*; D008297:Male; D051381:Rats; D017208:Rats, Wistar
D006639:Histidine; D006632:Histamine