We have previously demonstrated the presence of a cyclic GMP (cGMP)-dependent calcium-activated inward current in vascular smooth-muscle cells, and suggested this to be of importance in synchronizing smooth-muscle contraction. Here we demonstrate the characteristics of this current. Using conventional patch-clamp technique, whole-cell currents were evoked in freshly isolated smooth-muscle cells from rat mesenteric resistance arteries by elevation of intracellular calcium with either 10 mM caffeine, 1 microM BAY K8644, 0.4 microM ionomycin, or by high calcium concentration (900 nM) in the pipette solution. The current was found to be a calcium-activated chloride current with an absolute requirement for cyclic GMP (EC50 6.4 microM). The current could be activated by the constitutively active subunit of PKG. Current activation was blocked by the protein kinase G antagonist Rp-8-Br-PET-cGMP or with a peptide inhibitor of PKG, or with the nonhydrolysable ATP analogue AMP-PNP. Under biionic conditions, the anion permeability sequence of the channel was SCN- > Br- > I- > Cl- > acetate > F- >> aspartate, but the conductance sequence was I- > Br- > Cl- > acetate > F- > aspartate = SCN-. The current had no voltage or time dependence. It was inhibited by nickel and zinc ions in the micromolar range, but was unaffected by cobalt and had a low sensitivity to inhibition by the chloride channel blockers niflumic acid, DIDS, and IAA-94. The properties of this current in mesenteric artery smooth-muscle cells differed from those of the calcium-activated chloride current in pulmonary myocytes, which was cGMP-independent, exhibited a high sensitivity to inhibition by niflumic acid, was unaffected by zinc ions, and showed outward current rectification as has previously been reported for this current. Under conditions of high calcium in the patch-pipette solution, a current similar to the latter could be identified also in the mesenteric artery smooth-muscle cells. We conclude that smooth-muscle cells from rat mesenteric resistance arteries have a novel cGMP-dependent calcium-activated chloride current, which is activated by intracellular calcium release and which has characteristics distinct from other calcium-activated chloride currents.
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http://dx.doi.org/10.1085/jgp.200308972 | DOI Listing |
Nat Commun
December 2024
Whitehead Institute for Biomedical Research, Cambridge, MA, 02142, USA.
Although respiratory symptoms are the most prevalent disease manifestation of infection by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), nearly 20% of hospitalized patients are at risk for thromboembolic events. This prothrombotic state is considered a key factor in the increased risk of stroke, which is observed clinically during both acute infection and long after symptoms clear. Here, we develop a model of SARS-CoV-2 infection using human-induced pluripotent stem cell-derived endothelial cells (ECs), pericytes (PCs), and smooth muscle cells (SMCs) to recapitulate the vascular pathology associated with SARS-CoV-2 exposure.
View Article and Find Full Text PDFAlzheimers Dement
December 2024
Department of Psychology, University of Bath, Bath, UK.
Introduction: White matter hyperintensity volumes (WMHVs) are disproportionally prevalent in individuals with Alzheimer's disease (AD), potentially reflecting neurovascular injury. We quantify the association between AD polygenic risk score (AD-PRS) and WMHV, exploring single-nucleotide polymorphisms (SNPs) that are proximal to genes overexpressed in cerebrovascular cell species.
Methods: In a UK-Biobank sub-sample (mean age = 64, range = 45-81 years), we associate WMHV with (1) AD-PRS estimated via SNPs across the genome (minus apolipoprotein E [APOE] locus) and (2) AD-PRS estimated with SNPs proximal to specific genes that are overexpressed in cerebrovascular cell species.
Lasers Surg Med
December 2024
Department of Dermatology, Veterans Health Administration, San Antonio, Texas, USA.
Objectives: Glomangiomas are benign vascular malformations that exist within the spectrum of glomuvenous malformations which consist of varying amounts of glomus cells, vascular spaces, and smooth muscle. Glomangiomas are often treated due to associated pain, particularly when located on pressure areas such as the back or extensor surfaces, which can cause difficulty with certain activities and occupational functions. Histologically glomangiomas consist of prominent dilated vascular spaces lined by glomus cells typically situated in the deep-dermis to subcutaneous fat which limits treatment to modalities capable of reaching the depth of the tumor including excision, sclerotherapy, and laser therapy.
View Article and Find Full Text PDFFront Immunol
December 2024
Department of Thoracic and Cardiovascular Surgery, Seoul Metropolitan Government-Seoul National University (SMG-SNU) Boramae Medical Center, Seoul National University College of Medicine, Seoul, Republic of Korea.
Background: We investigated the effects of C-reactive protein (CRP) deposition on the vessel walls in abdominal aortic aneurysm (AAA) by analyzing spatially resolved changes in gene expression. Our aim was to elucidate the pathways that contribute to disease progression.
Methods: AAA specimens from surgically resected formalin-fixed paraffin-embedded tissues were categorized into the AAA-high CRP [serum CRP ≥ 0.
Cytojournal
November 2024
The Third School of Clinical Medicine, Southern Medical University, Guangzhou, Guangdong, China.
Objective: Hypertension significantly contributes to morbidity and mortality. Nuclear receptor subfamily 4 group a member 1 (Nur77) participates in regulating oxidative stress, but the mechanism in hypertension remains unclear. This study aimed to explore the function of Nur77 in oxidative stress induced by Angiotensin II (Ang II) in vascular smooth muscle cells (VSMCs) in hypertension.
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