Inhibitory action of a calcium channel blocker (nimodipine) on seizures and brain damage induced by pilocarpine and lithium-pilocarpine in rats.
The present work studied the effect of a calcium channel blocker (nimodipine) on rat behavioural changes and brain lesions observed after seizures induced by high doses of pilocarpine (400 mg/kg, s.c.; P400), and the association of lithium (3 mEq/kg, i.p., daily during 7 days) plus pilocarpine (a single dose of 15 mg/kg, s.c.) administered 24 h after the last injection of lithium. In the P400 model, nimodipine (5 or 10 mg/kg, i.p.) inhibited convulsions, status epilepticus, and significantly decreased the percentage of death and cerebral changes (Mann-Whitney, P = 0.0057). In the lithium-pilocarpine (Li-Pi) induced seizures, nimodipine even increased convulsive action and did not interfere with brain lesions. The results suggested that a calcium channel mechanism is involved in the P400 induced seizures, and that there is a difference in the physiopathology of epileptic seizures and brain damage induced by either P400 and Li-Pi models.
Marinho
M M
MM
Department of Physiology and Pharmacology, Federal University of Ceará, Brazil.
de Bruin
V M
VM
de Sousa
F C
FC
Aguiar
L M
LM
de Pinho
R S
RS
Viana
G S
GS
D000818:Animals; D001285:Atropine / Q000627:therapeutic use; D001927:Brain Diseases / Q000139:chemically induced / Q000473:pathology / Q000517:prevention & control*; D008094:Lithium; D008297:Male; D009553:Nimodipine / Q000627:therapeutic use*; D010862:Pilocarpine; D051381:Rats; D017208:Rats, Wistar; D012640:Seizures / Q000139:chemically induced / Q000517:prevention & control*; D013226:Status Epilepticus / Q000517:prevention & control
D010862:Pilocarpine; D009553:Nimodipine; D001285:Atropine; D008094:Lithium