RT Journal Article
SR Electronic
T1 Low levels of muscarinic M1 receptor–positive neurons in cortical layers III and V in Brodmann areas 9 and 17 from individuals with schizophrenia
JF Journal of Psychiatry and Neuroscience
JO J Psychiatry Neurosci
FD Canadian Medical Association
SP 338
OP 346
DO 10.1503/jpn.170202
VO 43
IS 5
A1 Scarr, Elizabeth
A1 Hopper, Shaun
A1 Vos, Valentina
A1 Seo, Myoung Suk
A1 Everall, Ian Paul
A1 Aumann, Timothy Douglas
A1 Chana, Gursharan
A1 Dean, Brian
YR 2018
UL http://jpn.ca/content/43/5/338.abstract
AB Background: Results of neuroimaging and postmortem studies suggest that people with schizophrenia may have lower levels of muscarinic M1 receptors (CHRM1) in the cortex, but not in the hippocampus or thalamus. Here, we use a novel immunohistochemical approach to better understand the likely cause of these low receptor levels.Methods: We determined the distribution and number of CHRM1-positive (CHRM1+) neurons in the cortex, medial dorsal nucleus of the thalamus and regions of the hippocampus from controls (n = 12, 12 and 5, respectively) and people with schizophrenia (n = 24, 24 and 13, respectively).Results: Compared with controls, levels of CHRM1+ neurons in people with schizophrenia were lower on pyramidal cells in layer III of Brodmann areas 9 (−44%) and 17 (−45%), and in layer V in Brodmann areas 9 (−45%) and 17 (−62%). We found no significant differences in the number of CHRM1+ neurons in the medial dorsal nucleus of the thalamus or in the hippocampus.Limitations: Although diagnostic cohort sizes were typical for this type of study, they were relatively small. As well, people with schizophrenia were treated with antipsychotic drugs before death.Conclusion: The loss of CHRM1+ pyramidal cells in the cortex of people with schizophrenia may underpin derangements in the cholinergic regulation of GABAergic activity in cortical layer III and in cortical/subcortical communication via pyramidal cells in layer V.