Monosodium l-glutamate-induced convulsions: changes in uptake and release of catecholamines in cerebral cortex and caudate nucleus of adult rats

• Published in: Epilepsy research Vol. 4; no. 1; pp. 20 - 27
• Main Authors: Beas-Zárate, Carlos, Schliebs, Reinhard, Morales-Villagran, Alberto, Feria-Velasco, Alfredo
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.07.1989; Elsevier
• Subjects: Animals; Biological and medical sciences; Catecholamines - pharmacokinetics; Caudate nucleus; Caudate Nucleus - metabolism; Cerebral cortex; Cerebral Cortex - metabolism; Convulsants - pharmacology; Dopamine release; Dopamine uptake; Glutamate-induced convulsions; Glutamates - pharmacology; In Vitro Techniques; Male; Medical sciences; Nervous system involvement in other diseases. Miscellaneous; Neurology; Norepinephrine release; Norepinephrine uptake; Rat brain slices; Rats; Rats, Inbred Strains; Seizures - chemically induced; Seizures - metabolism; Sodium Glutamate - pharmacology; Synaptosomes - metabolism; Dopamine uptake; Cerebral cortex; Dopamine release; Caudate nucleus; Rat brain slices; Norepinephrine release; Glutamate-induced convulsions; Norepinephrine uptake; Nervous system diseases; Intraperitoneal administration; Dopamine; Rat; Pathogenesis; Epilepsy; Rodentia; Catecholamine; Glutamate; Vertebrata; Experimental disease; Mammalia; Animal; Neurotransmitter; Norepinephrine
• ISSN: 0920-1211; 1872-6844
• DOI: 10.1016/0920-1211(89)90054-5

Adult rats (60 days old) were injected intraperitoneally with 5 mg/g monosodium l-glutamate (MSG). During the convulsive period (1 h after injection), uptake and release of [ 3H]norepinephrine ( 3H-NE) and [ 14C]dopamine ( 14C-DA) were measured in a crude synaptosoma fraction and in slices of cerebral cortex and caudate nucleus, respectively. A significant reduction of 3H-NE uptake was detected in cortical slices (by 42%) and in synaptosomal fraction (by 33%) of rats treated with MSG, whereas K +-stimulated 3H-NE release was decreased by 32% and 39% in brain slices and in a synaptosomal fraction of cerebral cortex, respectively, in comparison with animals injected with 0.9% NaCl aqueous solution (PSS). In the caudate nucleus, 14C-DA uptake was increased by 100% in brain slices and by 36% in the synaptosomal fraction following MSG administration, whereas K +-stimulated 14C-DA release was enhanced by 80% in slices and by 25% in synaptosomes as compared to PSS-injected rats. Data suggest that catecholaminergic neurotransmission may play an important role in the etiopathology of convulsions in the experimental model using MSG.