RATIONALE: The role of the hippocampal dopaminergic system in mnemonic function has not been clarified yet. OBJECTIVE: We previously reported that the dopamine D2 receptor (D2R) is involved in the regulation of acethylcholin (ACh) release in the hippocampus. In this study, we further investigated ACh-dopamine (DA) interaction in the hippocampus and its involvement in mnemonic function. METHODS: For experiment 1, rats fed with Cholin (Ch)-deficient chow were used. We examined the effects of D2R antagonist, raclopride, on cognitive performance using a passive avoidance task. We further carried out in vivo microdialysis to assess the effect of infusion of D2R agonist, quinpirole, into the ventral hippocampus on its capacity to release ACh. For experiment 2, rats fed with normal chow were used. The performance of a radial arm maze task was assessed to examine the effects of hippocampal injection of D2R agonist, quinpirole, on memory impairment induced by scopolamine, a muscarinic ACh antagonist. RESULTS: In experiment 1, rats fed with Ch-deficient chow showed impaired performances indicated by prolonged latency on retention trials of a passive avoidance task following the hippocampal injection of D2R antagonist, and showed reduced capacity to release ACh following the injection of D2R agonist compared with rats fed with normal chow. In experiment 2, memory impairment induced by the intraperitoneal injection of scopolamine was ameliorated by the injection of D2R agonist into the ventral hippocampus. CONCLUSION: These results indicate the possible involvement of hippocampal ACh-DA interaction in mnemonic processing.
RATIONALE: The role of the hippocampal dopaminergic system in mnemonic function has not been clarified yet. OBJECTIVE: We previously reported that the dopamine D2 receptor (D2R) is involved in the regulation of acethylcholin (ACh) release in the hippocampus. In this study, we further investigated ACh-dopamine (DA) interaction in the hippocampus and its involvement in mnemonic function. METHODS: For experiment 1, rats fed with Cholin (Ch)-deficient chow were used. We examined the effects of D2R antagonist, raclopride, on cognitive performance using a passive avoidance task. We further carried out in vivo microdialysis to assess the effect of infusion of D2R agonist, quinpirole, into the ventral hippocampus on its capacity to release ACh. For experiment 2, rats fed with normal chow were used. The performance of a radial arm maze task was assessed to examine the effects of hippocampal injection of D2R agonist, quinpirole, on memory impairment induced by scopolamine, a muscarinic ACh antagonist. RESULTS: In experiment 1, rats fed with Ch-deficient chow showed impaired performances indicated by prolonged latency on retention trials of a passive avoidance task following the hippocampal injection of D2R antagonist, and showed reduced capacity to release ACh following the injection of D2R agonist compared with rats fed with normal chow. In experiment 2, memory impairment induced by the intraperitoneal injection of scopolamine was ameliorated by the injection of D2R agonist into the ventral hippocampus. CONCLUSION: These results indicate the possible involvement of hippocampal ACh-DA interaction in mnemonic processing.
Authors: N Kemppainen; M Laine; M P Laakso; V Kaasinen; K Någren; T Vahlberg; T Kurki; J O Rinne Journal: Eur J Neurosci Date: 2003-07 Impact factor: 3.386
Authors: Abdalla Bowirrat; Thomas J H Chen; Marlene Oscar-Berman; Margaret Madigan; Amanda Lh Chen; John A Bailey; Eric R Braverman; Mallory Kerner; John Giordano; Siobhan Morse; B William Downs; Roger L Waite; Frank Fornari; Zaher Armaly; Kenneth Blum Journal: Mol Neurobiol Date: 2012-02-28 Impact factor: 5.590
Authors: Alice Egerton; Mitul A Mehta; Andrew J Montgomery; Julia M Lappin; Oliver D Howes; Suzanne J Reeves; Vincent J Cunningham; Paul M Grasby Journal: Neurosci Biobehav Rev Date: 2009-05-27 Impact factor: 8.989
Authors: Patrick D Worhunsky; Gustavo A Angarita; Zu Wei Zhai; David Matuskey; Jean-Dominique Gallezot; Robert T Malison; Richard E Carson; Marc N Potenza Journal: Neuropsychopharmacology Date: 2020-10-02 Impact factor: 7.853