Background And Purpose: This study examined the interaction between 5-hydroxytryptamine1B (5-HT1B) receptors and 20-hydroxyeiscosatetraenoic acid (20-HETE) in contributing to the acute fall in regional cerebral blood flow (rCBF) after subarachnoid hemorrhage (SAH) in rats.
Methods: The effects of intracisternal injection of 0.3 mL of arterial blood, artificial cerebrospinal fluid, and 5-HT on rCBF and the levels of 20-HETE and 5-HT in cerebrospinal fluid were measured in rats pretreated with vehicle, a 5-HT1B receptor antagonist (isamoltane hemifumarate), or an inhibitor of the synthesis of 20-HETE (HET0016). The effects of HET0016 and isamoltane on the vasoconstrictor response and changes in [Ca2+]i to 5-HT were also studied in middle cerebral arteries and vascular smooth muscle cells isolated from these vessels.
Results: 20-HETE and 5-HT levels in cerebrospinal fluid rose from 172+/-10 to 629+/-44 ng/mL and from 6+/-4 to 1163+/-200 nmol/mL, respectively, after SAH. rCBF fell by 30% 10 minutes after SAH, and it remained at this level for the next 2 hours. Blockade of 5-HT1B receptors prevented the sustained fall in rCBF seen after SAH. Intracisternal injection of 5-HT mimicked SAH by increasing 20-HETE levels in cerebrospinal fluid to 475+/-94 ng/mL and reducing rCBF by 30%. Blockade of the synthesis of 20-HETE with HET0016 prevented the fall in rCBF produced by 5-HT. Isamoltane and HET0016 reduced the vasoconstrictor response of isolated MCA to 5-HT by >60% and diminished the rise in [Ca2+]i produced by 5-HT in vascular smooth muscle cells isolated from these arteries.
Conclusions: These results suggest that the release of 5-HT after SAH activates 5-HT1B receptors and the synthesis of 20-HETE and that 20-HETE contributes to the acute fall in rCBF by potentiating the vasoconstrictor response of cerebral vessels to 5-HT.
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http://dx.doi.org/10.1161/01.STR.0000065829.45234.69 | DOI Listing |
Childs Nerv Syst
January 2025
Department of Global Health, Faculty of Health Sciences, McMaster University, 1280 Main St W, Hamilton, ON, L8S 4L8, Canada.
Background: A giant encephalocele associated with Chiari malformation is a rare congenital anomaly from a cephalad neural tube defect. Early prenatal diagnosis and parental counseling are essential; as early surgical intervention can improve outcomes.
Methods: Between 2010 and 2023, twenty-seven newborns out of 43,815 delivered at our institution were diagnosed with encephaloceles, including seven cases of giant encephalocele associated with Chiari malformation type III.
Sensors (Basel)
December 2024
Department of Biomedical Engineering, Army Medical University, The Third Military Medical University, Chongqing 400038, China.
Magnetic induction phase shift is a promising technology for the detection of cerebral hemorrhage, owing to its nonradioactive, noninvasive, and real-time detection properties. To enhance the detection sensitivity and linearity, a zero-flow sensor was proposed. The uniform primary magnetic field and its counteraction were achieved.
View Article and Find Full Text PDFInt J Mol Sci
January 2025
Department of Physiology and Pharmacology "Vittorio Erspamer", Sapienza University of Rome, 00185 Rome, Italy.
Patients with mild cognitive impairment due to Alzheimer's disease (ADMCI) typically show abnormally high delta (<4 Hz) and low alpha (8-12 Hz) rhythms measured from resting-state eyes-closed electroencephalographic (rsEEG) activity. Here, we hypothesized that the abnormalities in rsEEG activity may be greater in ADMCI patients than in those with MCI not due to AD (noADMCI). Furthermore, they may be associated with the diagnostic cerebrospinal fluid (CSF) amyloid-tau biomarkers in ADMCI patients.
View Article and Find Full Text PDFInt J Mol Sci
December 2024
Ace Alzheimer Center Barcelona, Universitat Internacional de Catalunya, 08029 Barcelona, Spain.
High-throughput proteomic platforms are crucial to identify novel Alzheimer's disease (AD) biomarkers and pathways. In this study, we evaluated the reproducibility and reliability of aptamer-based (SomaScan 7k) and antibody-based (Olink Explore 3k) proteomic platforms in cerebrospinal fluid (CSF) samples from the Ace Alzheimer Center Barcelona real-world cohort. Intra- and inter-platform reproducibility were evaluated through correlations between two independent SomaScan assays analyzing the same samples, and between SomaScan and Olink results.
View Article and Find Full Text PDFInt J Mol Sci
December 2024
Department of Biological, Geological and Environmental Sciences, University of Bologna, Via Selmi 3, 40126 Bologna, Italy.
This study aimed to investigate β-Caryophyllene (BCA) pharmacokinetics as well as the potential antitumor activity and mechanism of action of BCA and eugenol (EU), alone or in combination, in U87 glioblastoma (GB) cells. The BCA pharmacokinetic was studied by evaluating its concentration profiles in rat blood and cerebrospinal fluid after oral and intravenous administration. EU and BCA antitumor mechanisms were assessed by comparing their effects in U87 GB cells and non-tumoral HMC3 cells.
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