The purpose of the present study was to define the indirect central effect of hydrogen sulfide (H(2)S) on baroreflex control of sympathetic outflow. Perfusing the isolated carotid sinus with sodium hydrosulfide (NaHS), a H(2)S donor, the effect of H(2)S was measured by recording changes of renal sympathetic nerve activity (RSNA) in anesthetized male rats. Perfusion of isolated carotid sinus with NaHS (25, 50, 100 micromol/l) dose and time-dependently inhibited sympathetic outflow. Preconditioning of glibenclamide (20 micromol/l), a ATP-sensitive K(+) channels (K(ATP)) blocker, the above effect of NaHS was removed. With 1, 4-dihydro-2, 6-dimethyl-5-nitro-4-(2-[trifluoromethyl] phenyl) pyridine-3-carboxylic acid methyl ester (Bay K8644, 500 nmol/l) pretreatment, which is an agonist of L-calcium channels, the effect of NaHS was eliminated. Perfusion of cystathionine gamma-lyase (CSE) inhibitor, DL-propargylglycine (PPG, 200 micromol/l), increased sympathetic outflow. The results show that exogenous H(2)S in the carotid sinus inhibits sympathetic outflow. The effect of H(2)S is attributed to opening K(ATP) channels and closing the L-calcium channels.
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http://dx.doi.org/10.33549/physiolres.933050 | DOI Listing |
J Clin Neurosci
January 2025
Department of Neurological Surgery and Rosa Ella Burkhardt Brain Tumor & Neuro-Oncology Center, Cleveland Clinic, Cleveland, OH, USA; Cleveland Clinic Lerner College of Medicine of Case Western Reserve University. Electronic address:
Background And Objective: Radiosurgery can serve as a primary, adjuvant, or salvage treatment modality for cavernous sinus tumors (CST), providing high tumor control. However, particularly with cavernous sinus expansion, there may be insufficient distance from the optic apparatus to perform radiosurgery safely. The internal carotid artery adjacent to the distal dural ring (ICAddr), when enhancing similarly to the CST, can be difficult to delineate, and can lead to over-contouring of target volume near the optic nerve and therefore increasing the risk of radiation-induced optic toxicity.
View Article and Find Full Text PDFQuant Imaging Med Surg
January 2025
Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Background: The scanning trigger threshold affects image quality. The aim of this study was to investigate the effect of different scanning trigger thresholds on brain computed tomography angiography (CTA) image quality.
Methods: In this prospective study, 80 patients undergoing brain CTA examinations with dual-layer CT (DLCT) were randomly divided into group A and group B, with 40 patients in each group.
J Clin Exp Dent
December 2024
PhD, Universidade Federal do Ceará, Fortaleza, Ceará, Brazil.
Background: This study aims to assess the relationships between sphenoid sinus (SS) types, septation, lobulation, symmetry, septal deviation, and the variations in SS pneumatization regarding the surrounding neurovascular structures using Computed tomography (CT) images. Sexes and age groups were investigated.
Material And Methods: We retrospectively evaluated head CT-scans of 320 patients (age range 18-49 years); mean of 43.
Cureus
December 2024
Department of Ophthalmology, Hospital University Kebangsaan Malaysia, Kuala Lumpur, MYS.
We report a rare case of a missed intracavernous internal carotid artery dissecting aneurysm occurring as a complication of the base of skull fracture with severe brain injury causing acute cavernous sinus syndrome with permanent vision loss. A 31-year-old Myanmar lady had an alleged motor vehicle accident and suffered severe traumatic brain injury with multiple intracranial bleeds, multiple facial bone and base of skull fractures, and limb fractures. At one week post-trauma, she had severe right eye proptosis with vision loss, ophthalmoplegia, chemosis, and high intraocular pressure.
View Article and Find Full Text PDFEur Heart J
December 2024
Department of Cardiology, IRCCS Istituto Auxologico Italiano, Faint and Fall Research Centre, S. Luca Hospital, Piazzale Brescia 20, Milano 20149, Italy.
Background And Aims: Identifying the haemodynamic mechanism of autonomic syncope is the essential pre-requisite for effective and personalized therapy aimed at preventing recurrences. The present study assessed the diagnostic efficacy of a two-step assessment.
Methods: Multicentre prospective, cross-sectional, observational study.
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