We described an extensive network of cortical pyramidal neurons in the human brain with abundant acetylcholinesterase (AChE) activity. Emergence of these neurons during childhood/adolescence, attainment of highest density in early adulthood, and virtual absence in other species led us to hypothesize involvement of AChE within these neurons in higher cortical functions. The current study quantified the density and staining intensity of these neurons using histochemical procedures. Few faintly stained AChE-positive cortical pyramidal neurons were observed in children/adolescents. These neurons attained their highest density and staining intensity in young adulthood. Compared with the young adult group, brains of cognitively normal elderly displayed no significant change in numerical density but a significant decrease in staining intensity of AChE-positive cortical pyramidal neurons. Brains of elderly above age 80 with unusually preserved memory performance (SuperAgers) showed significantly lower staining intensity and density of these neurons when compared with same-age peers. Conceivably, low levels of AChE activity could enhance the impact of acetylcholine on pyramidal neurons to counterbalance other involutional factors that mediate the decline of memory capacity during average aging. We cannot yet tell if elderly with superior memory capacity have constitutively low neuronal AChE levels or if this feature reflects adaptive neuroplasticity.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6059146 | PMC |
http://dx.doi.org/10.1093/cercor/bhx047 | DOI Listing |
Biomedicines
December 2024
Department of Oral Biology, Semmelweis University, H-1089 Budapest, Hungary.
Background: N-methyl-D-aspartate type glutamate receptors (NMDARs) are fundamental to neuronal physiology and pathophysiology. The prefrontal cortex (PFC), a key region for cognitive function, is heavily implicated in neuropsychiatric disorders, positioning the modulation of its glutamatergic neurotransmission as a promising therapeutic target. Our recently published findings indicate that AT receptor activation enhances NMDAR activity in layer V pyramidal neurons of the rat PFC.
View Article and Find Full Text PDFNeurobiol Dis
January 2025
Division of Biomedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL, Canada. Electronic address:
The consequences of non-pathogenic huntingtin (HTT) reduction in the mature brain are of substantial importance as clinical trials for numerous HTT-lowering therapies are underway; many of which are non-selective in that they reduce both mutant and wild type protein variants. In this study, we injected CaMKII-promoted AAV-Cre directly into the hippocampus of adult HTT floxed mice to explore the role of wild-type huntingtin (wtHTT) in adult hippocampal pyramidal neurons and the broader implications of its loss. Our findings reveal that wtHTT depletion results in profound macroscopic morphological abnormalities in hippocampal structure, accompanied by significant reactive gliosis.
View Article and Find Full Text PDFCells
January 2025
IDDRC, Jane and Terry Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA.
Abnormalities in the mammalian target of the rapamycin (mTOR) pathway have been implicated in numerous developmental brain disorders. While the molecular and histological abnormalities have been described, less is known about alterations in membrane and synaptic excitability with chronic changes in the mTOR pathway. In the present study, we used a conditional mouse model with a deletion of the phosphatase and tensin homologue (Pten, a negative regulator of mTOR) from cortical pyramidal neurons (CPNs).
View Article and Find Full Text PDFBiol Psychiatry
January 2025
Translational Neuroscience Program, Department of Psychiatry, School of Medicine, University of Pittsburgh; Department of Neuroscience, Dietrich School of Arts and Sciences, University of Pittsburgh; Center for the Neural Basis of Cognition, Carnegie Mellon University. Electronic address:
Background: Certain cognitive processes require inhibition provided by the somatostatin (SST) class of gamma-aminobutyric acid (GABA) neurons in the dorsolateral prefrontal cortex (DLPFC). This inhibition onto pyramidal neuron dendrites depends on both SST and GABA signaling. Although SST mRNA levels are lower in the DLPFC in schizophrenia, it is not known if SST neurons exhibit alterations in the capacity to synthesize GABA, principally via the 67-kilodalton isoform of glutamic acid decarboxylase (GAD67).
View Article and Find Full Text PDFBrain
January 2025
Department of Neurology, The First Affiliated Hospital, Guangzhou Medical University, Guangzhou 510120, China.
Epilepsy is a network disorder, involving neural circuits at both the micro- and macroscale. While local excitatory-inhibitory imbalances are recognized as a hallmark at the microscale, the dynamic role of distinct neuron types during seizures remain poorly understood. At the macroscale, interactions between key nodes within the epileptic network, such as the central median thalamic nucleus (CMT), are critical to the, hippocampal epileptic process.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!