Dopaminergic modulation of LTP induction in the dentate gyrus of intact brain.
The effect of the dopamine system on the induction of long-term potentiation (LTP) in the dentate gyrus was studied in anesthetized rats. A subthreshold tetanic train (seven pulses at 100 Hz) given to the perforant pathway, which usually fails to elicit LTP, potentiated a slope of field excitatory postsynaptic potentiation (fEPSP) measured from the hilus of the dentate gyrus when a precursor for catecholamine, L-3,4-dihydroxyphenylalanine (L-DOPA), was administered orally to rats. The increase in the fEPSP slope persisted for at least 60 min. Intraventricular injection of a specific dopamine D1/D5 agonist, SKF38393, mimicked the effect of L-DOPA, suggesting an involvement of D1/D5 receptors in the induction of dentate gyrus LTP. Consistent with this, intraventricular administration of the D1/D5 antagonist SCH23390 resulted in complete inhibition of LTP induction by a longer tetanus (100 pulses at 100 Hz), which usually elicits a robust LTP. Thus, D1/D5 receptor activation appears to modulate LTP induction in vivo.
Kusuki
T
T
Mitsubishi Kasei Institute of Life Sciences, Tokyo, Japan.
Imahori
Y
Y
Ueda
S
S
Inokuchi
K
K
D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine / Q000494:pharmacology; D000768:Anesthesia, General; D000818:Animals; D001552:Benzazepines / Q000494:pharmacology; D001921:Brain / Q000502:physiology*; D018891:Dentate Gyrus / Q000502:physiology*; D004298:Dopamine / Q000502:physiology*; D015259:Dopamine Agents / Q000494:pharmacology; D018491:Dopamine Agonists / Q000494:pharmacology; D018492:Dopamine Antagonists / Q000494:pharmacology; D004558:Electric Stimulation; D004594:Electrophysiology; D007150:Immunohistochemistry; D007980:Levodopa / Q000494:pharmacology; D017774:Long-Term Potentiation / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D017447:Receptors, Dopamine D1 / Q000037:antagonists & inhibitors / Q000502:physiology; D050641:Receptors, Dopamine D5
D001552:Benzazepines; D015259:Dopamine Agents; D018491:Dopamine Agonists; D018492:Dopamine Antagonists; C493607:Drd5 protein, rat; D017447:Receptors, Dopamine D1; D050641:Receptors, Dopamine D5; D007980:Levodopa; D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine; D004298:Dopamine