Journal Article

Selective cognitive dysfunction in acetylcholine M1 muscarinic receptor mutant mice

Rahnama, Nancy P., Anagnostaras, Stephan G., Hamilton, Susan E., Nathanson, Neil M., Mitchell, Scott L., Murphy, Geoffrey G., Silva, Alcino J.

2003

Overview

Blockade of cholinergic neurotransmission by muscarinic receptor antagonists produces profound deficits in attention and memory. However, the antagonists used in previous studies bind to more than one of the five muscarinic receptor subtypes. Here we examined memory in mice with a null mutation of the gene coding the M 1 receptor, the most densely distributed muscarinic receptor in the hippocampus and forebrain. In contrast with previous studies using nonselective pharmacological antagonists, the M 1 receptor deletion produced a selective phenotype that included both enhancements and deficits in memory. Long-term potentiation (LTP) in response to theta burst stimulation in the hippocampus was also reduced in mutant mice. M 1 null mutant mice showed normal or enhanced memory for tasks that involved matching-to-sample problems, but they were severely impaired in non-matching-to-sample working memory as well as consolidation. Our results suggest that the M 1 receptor is specifically involved in memory processes for which the cortex and hippocampus interact.

• Publisher: Nature Publishing Group US,Nature Publishing Group
• Subject: Acetylcholine / Acetylcholine - metabolism / Animal Genetics and Genomics / Animals / Behavioral Sciences / Biological Techniques / Biomedical and Life Sciences / Biomedicine / Cerebral Cortex - metabolism / Cerebral Cortex - physiopathology / Cognition disorders / Conditioning (Psychology) - physiology / Cues / Diagnosis / Discrimination Learning - physiology / Electric Stimulation / Fear - physiology / Female / Genes / Hippocampus - metabolism / Hippocampus - physiopathology / Male / Maze Learning - physiology / Memory - physiology / Memory Disorders - genetics / Memory Disorders - metabolism / Memory Disorders - physiopathology / Memory, Short-Term - physiology / Mice / Mice, Knockout / Mutation / Neural Pathways - metabolism / Neural Pathways - physiopathology / Neurobiology / Neurosciences / Phenotype / Physiological aspects / Receptor, Muscarinic M1 / Receptors / Receptors, Muscarinic - deficiency / Receptors, Muscarinic - genetics / Risk factors