Effects of acute toxic doses of psychostimulants on extracellular levels of excitatory amino acids and taurine in rats: comparison of d-amphetamine and sydnocarb.
We used microdialysis to study how acute toxic doses of d-amphetamine and sydnocarb [3-(beta-phenylisopropyl)-N-phenylcarbamoylsydnonimine], an original Russian psychostimulant, affect extracellular levels of glutamate, aspartate, and taurine in the neostriatum of halothane-anesthetized male Sprague-Dawley rats. The administration of d-amphetamine (5.0 mg/kg x 4 i.p.) caused gradual fivefold increases in the extracellular glutamate and taurine levels and moderate increases in the extracellular aspartate level. Sydnocarb administration (23.8 mg/kg x 4 i.p., a dose equimolar to 5.0 mg/kg d-amphetamine) elicited a marked increase in the extracellular aspartate level and a small increase in the extracellular level of glutamate. The extracellular taurine level increased only after the last (fourth) injection. We conclude that a massive increase in extracellular taurine reflects hyperactivation of glutamatergic neurotransmission elicited by acute toxic dose of d-amphetamine. Sydnocarb seems to be less neurotoxic than d-amphetamine, because it elicits lesser changes in the extracellular levels of glutamate and taurine.
Anderzhanova
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E
Brain Research Center, University of Tampere, Medical School, Tampere, Finland. anderzhanova@hotmail.com
Rayevsky
K S
KS
Saransaari
P
P
Riitamaa
E
E
Oja
S S
SS
D000818:Animals; D000697:Central Nervous System Stimulants / Q000633:toxicity*; D002851:Chromatography, High Pressure Liquid; D003913:Dextroamphetamine / Q000633:toxicity; D018846:Excitatory Amino Acids / Q000378:metabolism*; D005110:Extracellular Space / Q000187:drug effects / Q000502:physiology; D007700:Kinetics; D008297:Male; D017551:Microdialysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D013558:Sydnones / Q000633:toxicity*; D013654:Taurine / Q000378:metabolism*
D000697:Central Nervous System Stimulants; D018846:Excitatory Amino Acids; D013558:Sydnones; D013654:Taurine; D003913:Dextroamphetamine; C009257:sidnocarb