Normal extracellular calcium levels block kindled seizures.
Seizures induced in animals by the kindling procedure have been described as an effective model of human epilepsy, principally because of the long lasting nature of this phenomenon (J. O. McNamara, 1984, Ann. Neurol. 16: 572-576). Permanent changes in the central nervous system associated with kindling should therefore provide insight onto of some forms of naturally occurring epilepsy. We report here the observation that in rats with fully developed kindled seizures, the exposure of the stimulation site to artificial cerebral spinal fluid (CSF) containing normal levels of calcium is able to block completely the seizure event. Exposure of the stimulation site to artificial CSF without calcium resulted in the return of the complete seizure. This implies that extracellular calcium levels are chronically reduced at the stimulation site of kindled rats and that this change in ion levels is necessary for the expression of the seizure.
Davies
G
G
Physiology and Pharmacology Academic Group, Hatfield Polytechnic, Herts., United Kingdom.
Peterson
D W
DW
D000818:Animals; D002118:Calcium / Q000134:cerebrospinal fluid / Q000502:physiology*; D006624:Hippocampus / Q000503:physiopathology; D007696:Kindling, Neurologic; D051381:Rats; D012640:Seizures / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control*
D002118:Calcium