Objective: The precise mechanism of action of vagus nerve stimulation (VNS) in suppressing epileptic seizures remains to be elucidated. This study investigates whether VNS modulates cortical excitability by determining the threshold for provoking focal motor seizures by cortical electrical stimulation before and after VNS.
Material And Methods: Male Wistar rats (n = 8) were implanted with a cuff-electrode around the left vagus nerve and with stimulation electrodes placed bilaterally on the rat motor cortex. Motor seizure threshold (MST) was assessed for each rat before and immediately after 1 h of VNS with standard stimulation parameters, during two to three sessions on different days.
Results: An overall significant increase of the MST was observed following 1 h of VNS compared to the baseline value (1420 microA and 1072 microA, respectively; P < 0.01). The effect was reproducible over time with an increase in MST in each experimental session.
Conclusions: VNS significantly increases the MST in a cortical stimulation model for motor seizures. These data indicate that VNS is capable of modulating cortical excitability.
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http://dx.doi.org/10.1111/j.1600-0404.2009.01223.x | DOI Listing |
Front Neurosci
January 2025
Department of Rehabilitation Medicine, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China.
Background: Multiple system atrophy-cerebellar subtype (MSA-C) is a predominance of cerebellar ataxia and autonomic failure. MSA-C has a rapid progression, with average 9 years from symptom onset to death. Despite its prevalence, there is still a lack of effective treatments.
View Article and Find Full Text PDFFront Neurosci
January 2025
Division of Medical Sciences, University of Victoria, Victoria, BC, Canada.
The vagus nerve (VN) is the primary parasympathetic nerve, providing two-way communication between the body and brain through a network of afferent and efferent fibers. Evidence suggests that altered VN signaling is linked to changes in the neuroimmune system, including microglia. Dysfunction of microglia, the resident innate immune cells of the brain, is associated with various neurodevelopmental disorders, including schizophrenia, attention deficit hyperactive disorder (ADHD), autism spectrum disorder (ASD), and epilepsy.
View Article and Find Full Text PDFiScience
February 2025
Department of Integrative Biology & Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA.
The vagus nerve is proposed to enable communication between the gut microbiome and the brain, but activity-based evidence is lacking. We find that mice reared germ-free exhibit decreased vagal tone relative to colonized controls, which is reversed via microbiota restoration. Perfusing antibiotics into the small intestines of conventional mice, but not germ-free mice, acutely decreases vagal activity which is restored upon re-perfusion with intestinal filtrates from conventional, but not germ-free, mice.
View Article and Find Full Text PDFCureus
December 2024
Clinical Research, National Institute of Neurology and Neurosurgery, Mexico City, MEX.
Anti-NMDA (N-methyl-D-aspartate) receptor encephalitis (ANRE) is a rare autoimmune condition targeting brain receptors, often linked to ovarian tumors in young women. In severe cases, it can lead to status epilepticus, but in sporadic cases, it may progress to super-refractory status epilepticus (SRSE), a dangerous state of continuous or repetitive seizures demanding urgent medical attention that continues or recurs more than 24 hours after the initiation of anesthetic therapy. We present a case report of anti-NMDA receptor limbic encephalitis-triggered SRSE terminated with vagus nerve stimulation (VNS) and titrated to high stimulation parameters in the immediate postoperative period.
View Article and Find Full Text PDFSurg Open Sci
January 2025
Department of Breast and Thyroid Surgery, Kitasato University Hospital/Kitasato University School of Medicine, Kanagawa, Japan.
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