Spinal nerve ligation: An experimental model to study neuropathic pain in rats and mice.

Neuropathic pain, defined as the most terrible of all tortures, which a nerve wound may inflict, is a common chronic painful condition caused by gradual damage or dysfunction of the somatosensory nervous system. As with many chronic diseases, neuropathic pain has a profound economic and emotional impact worldwide and represents a major public health issue from a treatment standpoint. This condition involves multiple sensory symptoms including impaired transmission and perception of noxious stimuli, burning, shooting, spontaneous pain, mechanical or thermal allodynia and hyperalgesia.

Lateral fluid percussion injury: A rat model of experimental traumatic brain injury.

Traumatic brain injury (TBI) represents one of the leading causes of disability and death worldwide. The annual economic impact of TBI-including direct and indirect costs-is high, particularly impacting low- and middle-income countries. Despite extensive research, a comprehensive understanding of the primary and secondary TBI pathophysiology, followed by the development of promising therapeutic approaches, remains limited.

Role of KCNK3 Dysfunction in Dasatinib-associated Pulmonary Arterial Hypertension and Endothelial Cell Dysfunction.

Pulmonary arterial (PA) hypertension (PAH) is a severe cardiopulmonary disease that may be triggered by exposure to drugs such as dasatinib or facilitated by genetic predispositions. The incidence of dasatinib-associated PAH is estimated at 0.45%, suggesting individual predispositions.

Distinct potassium channel types in brain capillary pericytes.

Capillaries, composed of electrically coupled endothelial cells and overlying pericytes, constitute the vast majority of blood vessels in the brain. The most arteriole-proximate three to four branches of the capillary bed are covered by α-actin-expressing, contractile pericytes. These mural cells have a distinctive morphology and express different markers compared with their smooth muscle cell (SMC) cousins but share similar excitation-coupling contraction machinery.

Ca3.1 channels facilitate calcium wave generation and myogenic tone development in mouse mesenteric arteries.

The arterial myogenic response to intraluminal pressure elicits constriction to maintain tissue perfusion. Smooth muscle [Ca] is a key determinant of constriction, tied to L-type (Ca1.2) Ca channels.

2023 ACR/EULAR antiphospholipid syndrome classification criteria.

Objective: To develop new antiphospholipid syndrome (APS) classification criteria with high specificity for use in observational studies and trials, jointly supported by the American College of Rheumatology (ACR) and EULAR.

Methods: This international multidisciplinary initiative included four phases: (1) Phase I, criteria generation by surveys and literature review; (2) Phase II, criteria reduction by modified Delphi and nominal group technique exercises; (3) Phase III, criteria definition, further reduction with the guidance of real-world patient scenarios, and weighting via consensus-based multicriteria decision analysis, and threshold identification; and (4) Phase IV, validation using independent adjudicators' consensus as the gold standard.

Results: The 2023 ACR/EULAR APS classification criteria include an entry criterion of at least one positive antiphospholipid antibody (aPL) test within 3 years of identification of an aPL-associated clinical criterion, followed by additive weighted criteria (score range 1-7 points each) clustered into six clinical domains (macrovascular venous thromboembolism, macrovascular arterial thrombosis, microvascular, obstetric, cardiac valve, and hematologic) and two laboratory domains (lupus anticoagulant functional coagulation assays, and solid-phase enzyme-linked immunosorbent assays for IgG/IgM anticardiolipin and/or IgG/IgM anti-β-glycoprotein I antibodies).

Vitamin D Receptor Deficiency Upregulates Pulmonary Artery Kv7 Channel Activity.

Recent evidence suggests that vitamin D is involved in the development of pulmonary arterial hypertension (PAH). The aim of this study was to analyze the electrophysiological and contractile properties of pulmonary arteries (PAs) in vitamin D receptor knockout mice (). PAs were dissected and mounted in a wire myograph.

The conducted vasomotor response and the principles of electrical communication in resistance arteries.

Biological tissues are fed by arterial networks whose task is to set blood flow delivery in accordance with energetic demand. Coordinating vasomotor activity among hundreds of neighboring segments is an essential process, one dependent upon electrical information spreading among smooth muscle and endothelial cells. The "conducted vasomotor response" is a functional expression of electrical spread, and it is this process that lies at the heart of this critical review.

Intraluminal pressure elevates intracellular calcium and contracts CNS pericytes: Role of voltage-dependent calcium channels.

Arteriolar smooth muscle cells (SMCs) and capillary pericytes dynamically regulate blood flow in the central nervous system in the face of fluctuating perfusion pressures. Pressure-induced depolarization and Ca elevation provide a mechanism for regulation of SMC contraction, but whether pericytes participate in pressure-induced changes in blood flow remains unknown. Here, utilizing a pressurized whole-retina preparation, we found that increases in intraluminal pressure in the physiological range induce contraction of both dynamically contractile pericytes in the arteriole-proximate transition zone and distal pericytes of the capillary bed.

Hydrogen sulfide as a neuromodulator of the vascular tone.

Hydrogen sulfide (HS) is a unique signaling molecule that, along with carbon monoxide and nitric oxide, belongs to the gasotransmitters family. HS is endogenously synthesized by enzymatic and non-enzymatic pathways. Three enzymatic pathways involving cystathionine-γ-lyase, cystathionine-β-synthetase, and 3-mercaptopyruvate sulfurtransferase are known as endogenous sources of HS.

Inward Rectifier Potassium Channels: Membrane Lipid-Dependent Mechanosensitive Gates in Brain Vascular Cells.

Cerebral arteries contain two primary and interacting cell types, smooth muscle (SMCs) and endothelial cells (ECs), which are each capable of sensing particular hemodynamic forces to set basal tone and brain perfusion. These biomechanical stimuli help confer tone within arterial networks upon which local neurovascular stimuli function. Tone development is intimately tied to arterial membrane potential (V ) and changes in intracellular [Ca] driven by voltage-gated Ca channels (VGCCs).

Adenosine signaling activates ATP-sensitive K channels in endothelial cells and pericytes in CNS capillaries.

The dense network of capillaries composed of capillary endothelial cells (cECs) and pericytes lies in close proximity to all neurons, ideally positioning it to sense neuron- and glial-derived compounds that enhance regional and global cerebral perfusion. The membrane potential () of vascular cells serves as the physiological bridge that translates brain activity into vascular function. In other beds, the ATP-sensitive K (K) channel regulates in vascular smooth muscle, which is absent in the capillary network.

The Large-Conductance, Calcium-Activated Potassium Channel: A Big Key Regulator of Cell Physiology.

Large-conductance Ca-activated K channels facilitate the efflux of K ions from a variety of cells and tissues following channel activation. It is now recognized that BK channels undergo a wide range of pre- and post-translational modifications that can dramatically alter their properties and function. This has downstream consequences in affecting cell and tissue excitability, and therefore, function.

Traumatic Brain Injury Impairs Systemic Vascular Function Through Disruption of Inward-Rectifier Potassium Channels.

Trauma can lead to widespread vascular dysfunction, but the underlying mechanisms remain largely unknown. Inward-rectifier potassium channels (Kir2.1) play a critical role in the dynamic regulation of regional perfusion and blood flow.

TRPA1 channel: New kid in the 'neurovascular coupling' town.

The just-in time delivery of oxygen and nutrients to active brain regions to support function (functional hyperemia; FH) is mediated by not yet fully understood mechanisms collectively referred to as 'neurovascular coupling' (NVC). In a recent publication (eLife 2021) Thakore et al. provide profound mechanistic insight how the capillary endothelial transient receptor potential ankyrin 1 (TRPA1) channel contribute to blood flow control and functional hyperemia in the brain.

Role of the α7 Nicotinic Acetylcholine Receptor in the Pathophysiology of Atherosclerosis.

Atherosclerosis constitutes a major risk factor for cardiovascular diseases, the leading cause of morbidity and mortality worldwide. This slowly progressing, chronic inflammatory disorder of large- and medium-sized arteries involves complex recruitment of immune cells, lipid accumulation, and vascular structural remodeling. The α7 nicotinic acetylcholine receptor (α7nAChR) is expressed in several cell types involved in the genesis and progression of atherosclerosis, including macrophages, dendritic cells, T and B cells, vascular endothelial and smooth muscle cells (VSMCs).

Impaired capillary-to-arteriolar electrical signaling after traumatic brain injury.

Traumatic brain injury (TBI) acutely impairs dynamic regulation of local cerebral blood flow, but long-term (>72 h) effects on functional hyperemia are unknown. Functional hyperemia depends on capillary endothelial cell inward rectifier potassium channels (Kir2.1) responding to potassium (K) released during neuronal activity to produce a regenerative, hyperpolarizing electrical signal that propagates from capillaries to dilate upstream penetrating arterioles.

Hematology and oncology clinical care during the coronavirus disease 2019 pandemic.

New York City has been at the epicenter of the coronavirus disease 2019 (COVID-19) pandemic that has already infected over a million people and resulted in more than 70,000 deaths as of early May 2020 in the United States alone. This rapid and enormous influx of patients into the health care system has had profound effects on all aspects of health care, including the care of patients with cancer. In this report, the authors highlight the transformation they underwent within the Division of Hematology and Medical Oncology as they prepared for the COVID-19 crisis in New York City.

K channels in the microvasculature: Regulatory properties and the lipid-hemodynamic environment.

Basal tone and perfusion control is set in cerebral arteries by the sensing of pressure and flow, key hemodynamic stimuli. These forces establish a contractile foundation within arterial networks upon which local neurovascular stimuli operate. This fundamental process is intimately tied to arterial V and the rise in cytosolic [Ca] by the graded opening of voltage-operated Ca channels.

A stepwise approach to resolving small ionic currents in vascular tissue.

Arterial membrane potential () is set by an active interplay among ion channels whose principal function is to set contractility through the gating of voltage-operated Ca channels. To garner an understanding of this electrical parameter, the activity of each channel must be established under near-physiological conditions, a significant challenge given their small magnitude. The inward rectifying K (K) channel is illustrative of the problem, as its outward "physiological" component is almost undetectable.

Intercellular Conduction Optimizes Arterial Network Function and Conserves Blood Flow Homeostasis During Cerebrovascular Challenges.

Objective: Cerebral arterial networks match blood flow delivery with neural activity. Neurovascular response begins with a stimulus and a focal change in vessel diameter, which by themselves is inconsequential to blood flow magnitude, until they spread and alter the contractile status of neighboring arterial segments. We sought to define the mechanisms underlying integrated vascular behavior and considered the role of intercellular electrical signaling in this phenomenon.

Prolonged activated partial thromboplastin time after prophylactic-dose unfractionated heparin in the post-operative neurosurgical setting: case series and management recommendations.

Primary brain tumors, both benign and malignant, pose a high risk of perioperative venous thromboembolism (VTE) due to the development of a prothrombotic state. Perioperative pharmacologic thromboprophylaxis with subcutaneous (SC) unfractionated heparin (UFH) has significantly reduced VTE associated morbidity. Recent reports suggest an association between prolonged activated partial thromboplastin time (aPTT) due to prophylactic SC UFH and increased bleeding risk.

Membrane Lipid-K2.x Channel Interactions Enable Hemodynamic Sensing in Cerebral Arteries.

Objective- Inward rectifying K (K) channels are present in cerebral arterial smooth muscle and endothelial cells, a tandem arrangement suggestive of a dynamic yet undiscovered role for this channel. This study defined whether distinct pools of cerebral arterial K channels were uniquely modulated by membrane lipids and hemodynamic stimuli. Approach and Results- A Ba-sensitive K current was isolated in smooth muscle and endothelial cells of rat cerebral arteries; molecular analyses subsequently confirmed K2.