The parvalbumin (PV)-positive neurons in the medial septum-diagonal band of Broca complex (MS-DB) play an important role in the generation of hippocampal theta rhythm involved in cognitive functions. These neurons in this region express a high density of 5-HT1A receptors which regulate the neuronal activity and consequently affect the theta rhythm. In this study, we examined changes in the theta-related firing activity of PV-positive neurons in the MS-DB, their response to 5-HT1A receptor stimulation and the corresponding hippocampal theta rhythm, and the density of PV-positive neurons and their co-localization with 5-HT1A receptors in rats with 6-hydroxydopamine lesions of the substantia nigra pars compacta (SNc). The lesion of the SNc decreased the rhythmically bursting activity of PV-positive neurons and the peak frequency of hippocampal theta rhythm. Systemic administration of 5-HT1A receptor agonist 8-OH-DPAT (0.5-128 µg/kg, i.v.) inhibited the firing rate of PV-positive neurons and disrupted rhythmically bursting activity of the neurons and the theta rhythm in sham-operated and the lesioned rats, respectively. The cumulative doses producing inhibition and disruption in the lesioned rats were higher than that of sham-operated rats. Furthermore, local application of 8-OH-DPAT (0.005 μg) in the MS-DB also inhibited the firing rate of PV-positive neurons and disrupted their rhythmically bursting activity in sham-operated rats, while having no effect on PV-positive neurons in the lesioned rats. The lesion of the SNc decreased the density of PV-positive neurons in the MS-DB, and percentage of PV-positive neurons expressing 5-HT1A receptors. These results indicate that the lesion of the SNc leads to suppression of PV-positive neurons in the MS-DB and hippocampal theta rhythm. Furthermore, the lesion decreases the response of these neurons to 5-HT1A receptor stimulation, which attributes to dysfunction and/or down-regulation of 5-HT1A receptor expression on these neurons. These changes may be involved in cognitive impairments of Parkinson's disease.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1002/hipo.22226 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Absolute number of three populations of interneurons and all GABAergic synapses in the human hippocampus.
J Neurosci
January 2025
Laboratory of Cerebral Cortex Research, HUN-REN Institute of Experimental Medicine, Budapest, Hungary
The human hippocampus, essential for learning and memory, is implicated in numerous neurological and psychiatric disorders, each linked to specific neuronal subpopulations. Advancing our understanding of hippocampal function requires computational models grounded in precise quantitative neuronal data. While extensive data exist on the neuronal composition and synaptic architecture of the rodent hippocampus, analogous quantitative data for the human hippocampus remain very limited.
View Article and Find Full Text PDFNeuronal mechanisms of nociceptive-evoked gamma-band oscillations in rodents.
Neuron
January 2025
State Key Laboratory of Cognitive Science and Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China; Department of Psychology, University of Chinese Academy of Sciences, Beijing, China. Electronic address:
Gamma-band oscillations (GBOs) in the primary somatosensory cortex (S1) play key roles in nociceptive processing. Yet, one crucial question remains unaddressed: what neuronal mechanisms underlie nociceptive-evoked GBOs? Here, we addressed this question using a range of somatosensory stimuli (nociceptive and non-nociceptive), neural recording techniques (electroencephalography in humans and silicon probes and calcium imaging in rodents), and optogenetics (alone or simultaneously with electrophysiology in mice). We found that (1) GBOs encoded pain intensity independent of stimulus intensity in humans, (2) GBOs in S1 encoded pain intensity and were triggered by spiking of S1 interneurons, (3) parvalbumin (PV)-positive interneurons preferentially tracked pain intensity, and critically, (4) PV S1 interneurons causally modulated GBOs and pain-related behaviors for both thermal and mechanical pain.
View Article and Find Full Text PDFLocalization of Melanocortin 1 Receptor in the Substantia Nigra.
Int J Mol Sci
December 2024
Department of Anatomy, Dokkyo Medical University School of Medicine, 880 Kita-Kobayashi, Mibu-machi, Shimotsuga-gun 321-0293, Tochigi, Japan.
Article Synopsis
- Recent research indicates that a deficiency in the melanocortin 1 receptor (MC1R) is linked to neurodegeneration similar to Parkinson's disease in a specific brain region called the substantia nigra (SN).
- The study used techniques like in situ hybridization and immunohistochemistry to identify the location and characteristics of MC1R, finding it mostly in susceptible dopaminergic neurons and in a type of inhibitory neuron known as parvalbumin (PV)-positive neurons.
- The results show that MC1R is involved not only in the cell membrane but also in organelles like mitochondria, suggesting that it, along with a modulator called attractin (Atrn), plays an important role in
Causal contributions of cell-type-specific circuits in the posterior dorsal striatum to auditory decision-making.
Cell Rep
December 2024
Institute of Neuroscience, Key Laboratory of Brain Cognition and Brain-inspired Intelligence Technology, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China; University of Chinese Academy of Sciences, Beijing 100049, China; Shanghai Center for Brain Science and Brain-Inspired Intelligence Technology, Shanghai 201210, China. Electronic address:
In the dorsal striatum (DS), the direct- and indirect-pathway striatal projection neurons (dSPNs and iSPNs) play crucial opposing roles in controlling actions. However, it remains unclear whether and how dSPNs and iSPNs provide distinct and specific contributions to decision-making, a process transforming sensory inputs to actions. Here, we perform causal interrogations on the roles of dSPNs and iSPNs in the posterior DS (pDS) in auditory-guided decision-making.
View Article and Find Full Text PDFPleiotrophin Overexpression Reduces Adolescent Ethanol Consumption and Modulates Ethanol-Induced Glial Responses and Changes in the Perineuronal Nets in the Mouse Hippocampus.
CNS Neurosci Ther
December 2024
Departamento de Ciencias Farmacéuticas y de la Salud, Facultad de Farmacia, Universidad san Pablo-CEU, CEU Universities, Urbanización Montepríncipe, Boadilla del Monte, Spain.
Aims: To investigate whether pleiotrophin (PTN) overexpression influences ethanol consumption during adolescence and its effects on glial responses, neurogenesis, and perineuronal nets (PNNs) in the mouse hippocampus.
Methods: Male and female adolescent transgenic mice with elevated PTN levels (Ptn-Tg) and controls underwent an intermittent access to ethanol (IAE) 2-bottle choice protocol. Ethanol consumption, PTN levels, neurogenesis, and glial responses were measured in the hippocampus.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!