Catecholamines in the rat brain during hypoglycemic convulsions and coma.
The purpose of the study was to investigate the relation between the catecholamines: noradrenaline and dopamine in the rat brain on one hand and hypoglycemic convulsions and coma on the other. Concentrations of noradrenaline in the hypothalamus, brain stem and cerebral cortex were decreased during hypoglycemic convulsions and were lower during coma than those during convulsions. Dopamine concentration in the striatum was decreased during convulsions and coma. It was shown that the decrease in concentration of catecholamines was a result of hypoglycemia but not of insulin action itself. Clonidine- alpha 2 agonist accelerated occurrence and prolonged duration of hypoglycemic convulsions. Haloperidol-dopamine receptor blocker had no effect on the time of occurrence or duration of convulsions and coma. The results indicate that noradrenaline may exert an inhibitory influence on hypoglycemic convulsions. No evidence has been provided to support involvement of dopamine in the control of hypoglycemic convulsions and coma.
Losy
J
J
Laboratory of Nervous System and Sensory Organs, Department of Physiology, School of Medicine, Poznań.
Bernat
R
R
D000818:Animals; D001921:Brain / Q000378:metabolism*; D003000:Clonidine / Q000494:pharmacology; D003128:Coma / Q000209:etiology / Q000378:metabolism*; D004298:Dopamine / Q000378:metabolism*; D005947:Glucose / Q000494:pharmacology; D006220:Haloperidol / Q000494:pharmacology; D007003:Hypoglycemia / Q000150:complications / Q000378:metabolism*; D007274:Injections, Intraperitoneal; D007328:Insulin / Q000494:pharmacology; D008297:Male; D009638:Norepinephrine / Q000378:metabolism*; D009994:Osmolar Concentration; D051381:Rats; D012640:Seizures / Q000209:etiology / Q000378:metabolism*; D014018:Tissue Distribution
D007328:Insulin; D005947:Glucose; D006220:Haloperidol; D003000:Clonidine; D004298:Dopamine; D009638:Norepinephrine