Age- and dose-specific anticonvulsant action of bumetanide in immature rats

• Main Author: Mareš, Pavel , 1937-
• Format: Article in Journal/Newspaper
• Language: unknown
• Subjects: Fyziologie člověka a srovnávací fyziologie; fyziologie; ontogeneze; krysa obecná; amino; physiology; ontogeny; Rattus rattus; chloride transporter; GABA (gamma-aminobutyric acid); pentylenetetrazol; 14; 612
• Online Access: https://kramerius.lib.cas.cz/view/uuid:deffdd61-e9fc-439b-b78e-252d46351a95

GABA exhibits depolarizing action in the immature neurons due to high intracellular activity of chloride ions. It is maintained by cation-chloride cotransporter NKCC1 which is present in immature brain. Bumetanide is a specific inhibitor of this cotransporter. We studied possible anticonvulsant activity of bumetanide in pentyl enetetrazol-induced seizures in three age groups of rat pups (7, 12, and 18 days old). Pretreatment with bumetanide (0.2-1 mg/kg i.p.) resulted in dose-dependent decrease of incidence of the tonic phase of generalized tonic-clonic seizures in 12-day-old rats only. No effect was observed in younger and older animals. Higher dose of bumetanide (2.5 mg/kg) did not affect tonic convulsions but, on the contrary, decreased latencies of generalized seizures in 12-day-old animals. Lack of marked anticonvulsant effect is probably due to relative maturity of neurons in the brainstem where the generator of generalized seizures is localized. Age- and dose-specific suppression of the tonic phase needs further analysis. Obsahuje seznam literatury