Dorsal hippocampal muscarinic acetylcholine and NMDA receptors disrupt water maze navigation.
The present study investigated the effects of bilateral dorsal hippocampal infusions with muscarinic acetylcholine (scopolamine; 3 and 10 micrograms per hemisphere) and N-methyl-D-aspartate (NMDA) (CPP; 0.01 and 0.03 microgram per hemisphere) antagonists on acquisition (drug delivered before daily training), consolidation (drug delivered after daily training) and retrieval (drug delivered only before spatial bias test) performance in a water maze (WM) spatial navigation test. Scopolamine 10 micrograms disrupted acquisition, but had no effect on consolidation or retrieval. CPP 0.03 microgram disrupted acquisition and retrieval behaviour. A combination of subthreshold doses of CPP (0.01 microgram) and scopolamine (3 micrograms) disrupted acquisition performance. The treatments did not disrupt navigation to a clearly visible escape platform. The present data indicate that dorsal hippocampal NMDA and muscarinic acetylcholine receptors are important for spatial navigation behaviour.
Riekkinen
M
M
University of Kuopio, Department of Neuroscience and Neurology, Finland.
Riekkinen
P
P
D000375:Aging / Q000502:physiology* / Q000523:psychology; D000704:Analysis of Variance; D000818:Animals; D018691:Excitatory Amino Acid Antagonists / Q000008:administration & dosage / Q000494:pharmacology*; D006624:Hippocampus / Q000254:growth & development / Q000502:physiology*; D007263:Infusions, Parenteral; D008297:Male; D018782:Maze Learning / Q000187:drug effects / Q000502:physiology*; D015999:Multivariate Analysis; D018727:Muscarinic Antagonists / Q000008:administration & dosage / Q000494:pharmacology; D010879:Piperazines / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D011976:Receptors, Muscarinic / Q000187:drug effects / Q000502:physiology*; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors / Q000187:drug effects / Q000502:physiology*; D012601:Scopolamine / Q000008:administration & dosage / Q000494:pharmacology*
D018691:Excitatory Amino Acid Antagonists; D018727:Muscarinic Antagonists; D010879:Piperazines; D011976:Receptors, Muscarinic; D016194:Receptors, N-Methyl-D-Aspartate; C050592:3-(2-carboxypiperazin-4-yl)propyl-1-phosphonic acid; D012601:Scopolamine