[Participation of D1 dopamine and alpha2 adrenoreceptors in formation of the frequency spectrum of the cortical activity in rats].
Intracerebroventricular injections of the alpha 2-adrenoreceptor agonist clonidine (1, 10, and 100 nmole) produced a dose-dependent decrease in the low-frequency (1.5-3.0 Hz) EEG components and increase in the EEG theta-rhythm (4.3-7.2 Hz) in freely moving rats with chronically implanted electrodes in the cortex and a cannule in the lateral ventricle. The beta-frequency EEG components (20.8-26.5 Hz) were stimulated by smaller doses of clonidine and reliably inhibited by the maximum doses. The alpha 2-adrenoreceptor antagonist yohimbine potentiated the effect of clonidine in the theta- and beta-ranges. The D1-dopaminergic receptor agonist SKF-38393 (100 nmole) reduced EEG intensity in the 1.9-2.5 and 9.3-13.8 Hz and increased intensity in the 4.9-5.7 and 20.3-26.5 Hz regions. Preliminary injection of the D1-antagonist SCH-23390 prevented from the agonist effects in the high-frequency part of the spectrum. The possible participation of the pre- and post-synaptic dopaminergic D1- and alpha 2-adrenergic receptors in the EEG profile variation under the action of the above agents is discussed.
Laboratory of Medical Biophysics, Russian Academy of Sciences, Pushchino, Moscow oblast, Russia.
E R
ER
Akhmetova
V V
VV
Vorob'ev
A V
AV
Groznyĭ
G I
GI
Kovalev
D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine / Q000494:pharmacology; D000316:Adrenergic alpha-Agonists / Q000494:pharmacology; D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000818:Animals; D001552:Benzazepines / Q000494:pharmacology; D003000:Clonidine / Q000494:pharmacology; D018491:Dopamine Agonists / Q000494:pharmacology; D018492:Dopamine Antagonists / Q000494:pharmacology; D004569:Electroencephalography; D007276:Injections, Intraventricular; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D018341:Receptors, Adrenergic, alpha-2 / Q000502:physiology*; D017447:Receptors, Dopamine D1 / Q000502:physiology*; D015016:Yohimbine / Q000494:pharmacology
D000316:Adrenergic alpha-Agonists; D000317:Adrenergic alpha-Antagonists; D001552:Benzazepines; D018491:Dopamine Agonists; D018492:Dopamine Antagonists; D018341:Receptors, Adrenergic, alpha-2; D017447:Receptors, Dopamine D1; D015016:Yohimbine; D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine; D003000:Clonidine