An alpha 2 antagonist, idazoxan, enhances EPSP-spike coupling in the rat dentate gyrus.
The effect of the alpha 2 antagonist, idazoxan (IDA), on the excitability of neurons in the dentate gyrus of the hippocampus was studied. Population field potentials (PS) evoked by stimulation of the perforant pathway were measured before and after drug treatment. IDA enhanced the amplitude of the PS, while decreasing the slope of the EPSP. Neurotoxic destruction of noradrenergic nerve terminals completely abolished the IDA effect, arguing that its mechanism of action is through enhanced release of noradrenaline (NA). It is proposed that NA enhances the EPSP-to-spike coupling component of the PS.
Richter-Levin
G
G
Center for Neuroscience, Weizmann Institute, Rehovot, Israel.
Segal
M
M
Sara
S
S
D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology*; D000704:Analysis of Variance; D000818:Animals; D001596:Benzylamines / Q000494:pharmacology; D004146:Dioxanes / Q000494:pharmacology*; D004558:Electric Stimulation; D005071:Evoked Potentials / Q000187:drug effects; D006624:Hippocampus / Q000187:drug effects / Q000502:physiology*; D019329:Idazoxan; D008297:Male; D009498:Neurotoxins / Q000494:pharmacology; D009638:Norepinephrine / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D012016:Reference Values
D000317:Adrenergic alpha-Antagonists; D001596:Benzylamines; D004146:Dioxanes; D009498:Neurotoxins; C012102:DSP 4; D009638:Norepinephrine; D019329:Idazoxan