Monosodium L-glutamate-induced convulsions: changes in uptake and release of catecholamines in cerebral cortex and caudate nucleus of adult rats.
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 synaptosomal 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.
Beas-Zárate
C
C
Facultad de Ciencias, Universidad de Guadalajara, Jalisco, Mexico.
Schliebs
R
R
Morales-Villagran
A
A
Feria-Velasco
A
A
D000818:Animals; D002395:Catecholamines / Q000493:pharmacokinetics*; D002421:Caudate Nucleus / Q000378:metabolism*; D002540:Cerebral Cortex / Q000378:metabolism*; D003292:Convulsants / Q000494:pharmacology*; D005971:Glutamates / Q000494:pharmacology*; D066298:In Vitro Techniques; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012640:Seizures / Q000139:chemically induced / Q000378:metabolism*; D012970:Sodium Glutamate / Q000494:pharmacology*; D013574:Synaptosomes / Q000378:metabolism
D002395:Catecholamines; D003292:Convulsants; D005971:Glutamates; D012970:Sodium Glutamate