Elucidating the role of muscarinic receptors in psychosis statistics on college dating
In this review we report recent findings on the physiological role of the five known muscarinic acetylcholine receptors (m ACh Rs) as shown by gene targeting technology.
Using knockout mice for each m ACh Rs subtype, the role of m ACh Rs subtypes in a number of physiological functions was confirmed and new activities were discovered.
In this context, it is of interest that M1 receptor knockout mice show abnormalities in memory-relative cognitive behaviors (Anagnostaras et al, 2003), whereas mice lacking the M4 receptor show a deficit in prepulse inhibition of the startle reflex, a measure of attention (Felder et al, 2001).
Recent studies using acetylcholinesterase inhibitors support the notion that activation of cholinergic receptors would be an effective approach to reversing the cognitive deficits in schizophrenia (Buchanan et al, 2003).
Furthermore, 0 of 4 SNPs within CHRM1 previously deduced from sequencing of the human genome were found in this study despite a prediction that a majority of such inferred SNPs are accurate.
As acetycholinesterase inhibitors are nonspecific in their effects, targeting both nicotinic and muscarinic receptors, it is difficult to assess the potential of each subtype as a target for remediation strategies and its role in side effects.
The genetic study by Liao et al (2003) suggests that involvement of M1 receptors might be critical in the genesis of cognitive deficits in schizophrenia, and therefore M1 receptor agonism might be a good remediation strategy for the treatment of the cognitive dysfunction in schizophrenia.
Of these, 8 represent synonymous SNPs, indicating that CHRM1 is highly conserved in humans.
Only a single allele was found to contain a nonsynonymous SNP, which encodes an amino acid change of Cys to Arg at position 417.