An investigation of the relationship between the dopaminergic and electroencephalographic effects of gamma-butyrolactone.
An investigation was made into the relationship between dopaminergic and EEG effects of gamma-butyrolactone (GBL) by comparing time-course and dose-response studies of these two actions of gamma-butyrolactone in rats implanted with permanent cortical electrodes. Dopaminergic effects were assessed by the changes induced by gamma-butyrolactone in the concentration of dopamine and dihydroxyphenylacetic acid (DOPAC) in the striatum and cortex. In addition, the effects of anticonvulsant drugs, known to overcome the EEG effects of gamma-butyrolactone, were assessed against the dopaminergic actions of this drug. The EEG changes induced by gamma-butyrolactone occurred with smaller doses, had an earlier onset and lasted longer than the elevation in striatal dopamine and DOPAC concentration induced by gamma-butyrolactone. There were marked sequential changes in EEG and behavior in the face of normal dopamine and DOPAC concentrations in animals given 200 mg/kg of gamma-butyrolactone. The anticonvulsants, ethosuximide and trimethadione, which abolish or attenuate seizure activity induced by gamma-butyrolactone, were effective in aborting or decreasing the rise in striatal dopamine concentration produced by gamma-butyrolactone. However, sodium valproate, also known to abolish or attenuate the EEG effects of gamma-butyrolactone exacerbated the dopamine effects of this compound. The elevation in dopamine produced by gamma-butyrolactone does not seem to be responsible for the EEG or behavioral effects seen with this substance.
D015102:3,4-Dihydroxyphenylacetic Acid / Q000378:metabolism; D015107:4-Butyrolactone / Q000494:pharmacology*; D000818:Animals; D000927:Anticonvulsants / Q000494:pharmacology; D002540:Cerebral Cortex / Q000187:drug effects; D003342:Corpus Striatum / Q000187:drug effects; D004298:Dopamine / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004569:Electroencephalography; D005071:Evoked Potentials / Q000187:drug effects; D005663:Furans / Q000494:pharmacology*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D011954:Receptors, Dopamine / Q000187:drug effects*; D012640:Seizures / Q000139:chemically induced
D000927:Anticonvulsants; D005663:Furans; D011954:Receptors, Dopamine; D015102:3,4-Dihydroxyphenylacetic Acid; D015107:4-Butyrolactone; D004298:Dopamine