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Journal of the American College of... Jan 2003
Topics: Coronary Artery Disease; Coronary Circulation; Coronary Stenosis; Humans; Myocardial Infarction; Polymorphism, Genetic; Receptors, Adrenergic, alpha; Risk Factors; Vasoconstriction
PubMed: 12535807
DOI: 10.1016/s0735-1097(02)02703-1 -
Journal of Biomedical Optics Aug 2023Corticosteroids-commonly prescribed medications for skin diseases-inhibit the secretion of vasodilators, such as prostaglandin, thereby exerting anti-inflammatory action...
SIGNIFICANCE
Corticosteroids-commonly prescribed medications for skin diseases-inhibit the secretion of vasodilators, such as prostaglandin, thereby exerting anti-inflammatory action by constricting capillaries in the dermis. The effectiveness of corticosteroids is determined by the degree of vasoconstriction followed by skin whitening, namely, the blanching effect. However, the current method of observing the blanching effect indirectly evaluates the effects of corticosteroids.
AIM
In this study, we employed optical-resolution photoacoustic (PA) microscopy (OR-PAM) to directly visualize the blood vessels and quantitatively evaluate vasoconstriction.
APPROACH
Using OR-PAM, the vascular density in mice skin was monitored for 60 min after performing each experimental procedure for four groups, and the vasoconstriction was quantified. Volumetric PA data were segmented into the papillary dermis, reticular dermis, and hypodermis based on the vascular characteristics obtained through OR-PAM. The vasoconstrictive effect of each skin layer was quantified according to the dermatological treatment method.
RESULTS
In the case of corticosteroid topical application, vasoconstriction was observed in the papillary ( ) and reticular ( ) dermis. For corticosteroid subcutaneous injection, constriction was observed solely in the reticular ( ) dermis. In contrast, no vasoconstrictions were observed with nonsteroidal topical application.
CONCLUSIONS
Our results indicate that OR-PAM can quantitatively monitor the vasoconstriction induced by corticosteroids, thereby validating OR-PAMs potential as a practical evaluation tool for predicting the effectiveness of corticosteroids in dermatology.
Topics: Animals; Mice; Anti-Inflammatory Agents; Skin; Adrenal Cortex Hormones; Vasoconstriction; Spectrum Analysis; Photoacoustic Techniques
PubMed: 36844430
DOI: 10.1117/1.JBO.28.8.082805 -
Circulation Journal : Official Journal... Mar 2009Atherothrombosis has long been recognized as an important mechanism of cardiac events in ischemic heart disease, and large multicenter clinical studies have shown the... (Review)
Review
Atherothrombosis has long been recognized as an important mechanism of cardiac events in ischemic heart disease, and large multicenter clinical studies have shown the benefit of antiplatelet agents, statins, beta-blockers and angiotensin converting enzyme inhibitors in preventing these events. However, more recent studies have been less successful at showing incremental gains in targeting these mechanisms, suggesting that the limits of this strategy have been exploited. Coronary vasoconstriction is another important mechanism in ischemic heart disease but has received little attention and yet is a potential therapeutic target. In the current review, the reasons why coronary vasconstriction has received insufficient consideration are explored. In particular, we need to change our approach from lumping heterogeneous clinical entities together to focusing on clinically-discrete homogeneous groups with a common mechanism and thus therapeutic target. The role of coronary vasoconstriction is examined in the various ischemic syndromes (variant angina, chronic stable angina, acute coronary syndromes and syndrome X) and the underlying mechanisms discussed. Finally, in order to advance studies in this field, an innovative research strategy is proposed, including: (1) selection of paradigmatic cases for the various ischemic syndromes; (2) candidate therapeutic targets; and (3) approaches in assessing the clinical efficacy of these potential therapies.
Topics: Angina Pectoris, Variant; Animals; Coronary Vasospasm; Humans; Myocardial Ischemia; Vasoconstriction; Vasodilator Agents
PubMed: 19202303
DOI: 10.1253/circj.cj-09-0033 -
Vascular Pharmacology Aug 2023Neuropeptide Y (NPY) is co-released with norepinephrine and ATP by sympathetic nerves innervating arteries. Circulating NPY is elevated during exercise and...
Neuropeptide Y (NPY) is co-released with norepinephrine and ATP by sympathetic nerves innervating arteries. Circulating NPY is elevated during exercise and cardiovascular disease, though information regarding the vasomotor function of NPY in human blood vessels is limited. Wire myography revealed NPY directly stimulated vasoconstriction (EC 10.3 ± 0.4 nM; N = 5) in human small abdominal arteries. Maximum vasoconstriction was antagonised by both BIBO03304 (60.7 ± 6%; N = 6) and BIIE0246 (54.6 ± 5%; N = 6), suggesting contributions of both Y and Y receptor activation, respectively. Y and Y receptor expression in arterial smooth muscle cells was confirmed by immunocytochemistry, and western blotting of artery lysates. α,β-meATP evoked vasoconstrictions (EC 282 ± 32 nM; N = 6) were abolished by suramin (IC 825 ± 45 nM; N = 5) and NF449 (IC 24 ± 5 nM; N = 5), suggesting P2X1 mediates vasoconstriction in these arteries. P2X1, P2X4 and P2X7 were detectable by RT-PCR. Significant facilitation (1.6-fold) of α,β-meATP-evoked vasoconstrictions was observed when submaximal NPY (10 nM) was applied between α,β-meATP applications. Facilitation was antagonised by either BIBO03304 or BIIE0246. These data reveal NPY causes direct vasoconstriction in human arteries which is dependent upon both Y and Y receptor activation. NPY also acts as a modulator, facilitating P2X1-dependent vasoconstriction. Though in contrast to the direct vasoconstrictor effects of NPY, there is redundancy between Y and Y receptor activation to achieve the facilitatory effect.
Topics: Humans; Neuropeptide Y; Vasoconstriction; Vasoconstrictor Agents; Receptors, Purinergic P2X1; Receptors, Neuropeptide Y; Arteries
PubMed: 37419269
DOI: 10.1016/j.vph.2023.107192 -
The Journal of Headache and Pain Feb 2024The pathophysiology of the reversible cerebral vasoconstriction syndrome (RCVS) remains enigmatic and the role of glymphatics in RCVS pathophysiology has not been...
BACKGROUND
The pathophysiology of the reversible cerebral vasoconstriction syndrome (RCVS) remains enigmatic and the role of glymphatics in RCVS pathophysiology has not been evaluated. We aimed to investigate RCVS glymphatic dynamics and its clinical correlates.
METHODS
We prospectively evaluated the glymphatic function in RCVS patients, with RCVS subjects and healthy controls (HCs) recruited between August 2020 and November 2023, by calculating diffusion-tensor imaging along the perivascular space (DTI-ALPS) index under a 3-T MRI. Clinical and vascular (transcranial color-coded duplex sonography) investigations were conducted in RCVS subjects. RCVS participants were separated into acute (≤ 30 days) and remission (≥ 90 days) groups by disease onset to MRI interval. The time-trend, acute stage and longitudinal analyses of the DTI-ALPS index were conducted. Correlations between DTI-ALPS index and vascular and clinical parameters were performed. Bonferroni correction was applied to vascular investigations (q = 0.05/11).
RESULTS
A total of 138 RCVS patients (mean age, 46.8 years ± 11.8; 128 women) and 42 HCs (mean age, 46.0 years ± 4.5; 35 women) were evaluated. Acute RCVS demonstrated lower DTI-ALPS index than HCs (p < 0.001) and remission RCVS (p < 0.001). A continuously increasing DTI-ALPS trend after disease onset was demonstrated. The DTI-ALPS was lower when the internal carotid arteries resistance index and six-item Headache Impact test scores were higher. In contrast, during 50-100 days after disease onset, the DTI-ALPS index was higher when the middle cerebral artery flow velocity was higher.
CONCLUSIONS
Glymphatic function in patients with RCVS exhibited a unique dynamic evolution that was temporally coupled to different vascular indices and headache-related disabilities along the disease course. These findings may provide novel insights into the complex interactions between glymphatic transport, vasomotor control and pain modulation.
Topics: Humans; Female; Middle Aged; Vasoconstriction; Cerebrovascular Disorders; Magnetic Resonance Imaging; Middle Cerebral Artery; Headache
PubMed: 38317074
DOI: 10.1186/s10194-024-01726-1 -
Experimental Physiology Jul 2007Neuronal activity in the central nervous system evokes localized changes in blood flow, a response termed neurovascular coupling or functional hyperaemia. Modern... (Review)
Review
Neuronal activity in the central nervous system evokes localized changes in blood flow, a response termed neurovascular coupling or functional hyperaemia. Modern functional imaging methods, such as functional magnetic resonance imaging (fMRI), measure signals related to functional hyperaemia in order to determine localization of brain function and to diagnose disease. The cellular mechanisms that underlie functional hyperaemia, however, are not well understood. Glial cells have been hypothesized to be intermediaries between neurons and blood vessels in the control of neurovascular coupling, owing to their ability to release vasoactive factors in response to neuronal activity. Using an in vitro preparation of the isolated, intact rodent retina, we have investigated two likely mechanisms of glial control of the vasculature: glial K(+) siphoning and glial induction of vasoactive arachidonic acid metabolites. Potassium siphoning is a process by which a K(+) current flowing through glial cells transfers K(+) released from active neurons to blood vessels. Since slight increases in extracellular K(+) can cause vasodilatation, this mechanism was hypothesized to contribute to neurovascular coupling. Our data, however, suggest that glial K(+) siphoning does not contribute significantly to neurovascular coupling in the retina. Instead, we suggest that glial cells mediate neurovascular coupling by inducing the production of two types of arachidonic acid metabolites, epoxyeicosatrienoic acids (EETs) and 20-hydroxyeicosatetraenoic acid (20-HETE), which dilate and constrict vessels, respectively. We show that both light flashes and direct glial stimulation produce vasodilatation or vasoconstriction mediated by EETs and 20-HETE, respectively. Further, we show that the type of vasomotor response observed (dilatation or constriction) depends on retinal levels of nitric oxide. Our data also demonstrate that glial cells are necessary intermediaries for signalling from neurons to blood vessels, since functional hyperaemia does not occur when neuron-to-glia communication is interrupted. These results indicate that glial cells play an important role in mediating functional hyperaemia and suggest that the regulation of blood flow may involve both vasodilating and vasoconstricting components.
Topics: Animals; Arachidonic Acid; Calcium Signaling; Light; Mice; Neuroglia; Potassium Channels, Inwardly Rectifying; Rats; Retina; Signal Transduction; Vasoconstriction; Vasodilation
PubMed: 17434916
DOI: 10.1113/expphysiol.2006.036376 -
The Journal of Headache and Pain Oct 2008Thunderclap headache attributed to reversible cerebral vasoconstriction (THARCV) is a syndrome observed in a number of reported cases. In this article we reviewed this... (Review)
Review
Thunderclap headache attributed to reversible cerebral vasoconstriction (THARCV) is a syndrome observed in a number of reported cases. In this article we reviewed this new headache entity (idiopathic form) using the clinical-radiological findings of 25 reported patients. In this series of patients 72% were women, the mean age at the onset of first headache episode was 39.4 +/- 2.3 years. In addition to the sine qua non condition of being abrupt and severe (thunderclap) at the onset, the headache was usually described as being explosive, excruciating, or crushing. The feature of pulsatility, accompanied or not by nausea was described by 80% of the patients. Forty percent of the cases manifested vomiting and 24% photophobia. Usually the headache was generalized, and in three cases it was unilateral at least at the onset. In 21 of 25 patients (84%) there was at least one recurrence or a sudden increase in the intensity of the headache. A past history of migraine was present in 52% of the patients. Precipitating factors were identified in 56% of the patients. Sexual intercourse was described by six patients. Of the 25 patients with THARCV syndrome studied, 12 (48%) developed focal neurological signs, transitory ischemic attack (n = 1), or ischemic stroke (n = 11, 44%), and two (8%) of them manifested seizures. The THARCV syndrome is a neurological disturbance perhaps more frequent than expected, preferentially affecting middle aged female migraineurs, and having an unpredictable prognosis, either showing a benign course or leading to stroke.
Topics: Adult; Female; Headache Disorders, Primary; Humans; Male; Middle Aged; Valsalva Maneuver; Vascular Diseases; Vasoconstriction; Young Adult
PubMed: 18668199
DOI: 10.1007/s10194-008-0054-6 -
AJNR. American Journal of Neuroradiology Oct 2020There is mounting evidence supporting the benefit of intra-arterial administration of vasodilators in diagnosing reversible cerebral vasoconstriction syndrome. We...
BACKGROUND AND PURPOSE
There is mounting evidence supporting the benefit of intra-arterial administration of vasodilators in diagnosing reversible cerebral vasoconstriction syndrome. We prospectively quantified the degree of luminal diameter dilation after intra-arterial administration of verapamil and its accuracy in diagnosing reversible cerebral vasoconstriction syndrome.
MATERIALS AND METHODS
Patients suspected of having intracranial arteriopathy on noninvasive imaging and referred for digital subtraction angiography were enrolled in a prospective registry. Intra-arterial verapamil was administered in vascular territories with segmental irregularities. The caliber difference (Caliber - Caliber) and the proportion of caliber change ([(Caliber - Caliber)/Caliber] × 100%) were used to determine the response to verapamil. The diagnosis of reversible cerebral vasoconstriction syndrome was made on the basis of clinical and imaging features at a follow-up appointment, independent of the reversibility of verapamil. Receiver operating characteristic curve analysis was performed to determine the best threshold.
RESULTS
Twenty-six patients were included, and 9 (34.6%) were diagnosed with reversible cerebral vasoconstriction syndrome. A total of 213 vascular segments were assessed on diagnostic angiography. Every patient with a final diagnosis of reversible cerebral vasoconstriction syndrome responded to intra-arterial verapamil. The maximal proportion of change (< .001), mean proportion of change (= .002), maximal caliber difference (= .004), and mean caliber difference (= .001) were statistically different between patients with reversible cerebral vasoconstriction syndrome and other vasculopathies. A maximal proportion of change ≥32% showed a sensitivity of 100% and a specificity of 88.2% to detect reversible cerebral vasoconstriction syndrome (area under the curve = 0.951). The Reversible Cerebral Vasoconstriction Syndrome-2 score of ≥5 points achieved a lower area under the curve (0.908), with a sensitivity of 77.8% and a specificity of 94.1%.
CONCLUSIONS
Objective measurement of the change in the arterial calibers after intra-arterial verapamil is accurate in distinguishing reversible cerebral vasoconstriction syndrome from other vasculopathies. A proportion of change ≥32% has the best diagnostic performance.
Topics: Adult; Angiography, Digital Subtraction; Female; Humans; Infusions, Intra-Arterial; Male; Middle Aged; Vasoconstriction; Vasodilator Agents; Vasospasm, Intracranial; Verapamil
PubMed: 32943423
DOI: 10.3174/ajnr.A6772 -
Physiological Reviews Apr 1999The vascular myogenic response refers to the acute reaction of a blood vessel to a change in transmural pressure. This response is critically important for the... (Review)
Review
The vascular myogenic response refers to the acute reaction of a blood vessel to a change in transmural pressure. This response is critically important for the development of resting vascular tone, upon which other control mechanisms exert vasodilator and vasoconstrictor influences. The purpose of this review is to summarize and synthesize information regarding the cellular mechanism(s) underlying the myogenic response in blood vessels, with particular emphasis on arterioles. When necessary, experiments performed on larger blood vessels, visceral smooth muscle, and even striated muscle are cited. Mechanical aspects of myogenic behavior are discussed first, followed by electromechanical coupling mechanisms. Next, mechanotransduction by membrane-bound enzymes and involvement of second messengers, including calcium, are discussed. After this, the roles of the extracellular matrix, integrins, and the smooth muscle cytoskeleton are reviewed, with emphasis on short-term signaling mechanisms. Finally, suggestions are offered for possible future studies.
Topics: Animals; Homeostasis; Humans; Muscle, Smooth, Vascular; Signal Transduction; Vasoconstriction; Vasodilation
PubMed: 10221985
DOI: 10.1152/physrev.1999.79.2.387 -
Translational Vision Science &... Aug 2020Endothelin-1 (ET-1) is a potent vasoactive factor implicated in development of diabetic retinopathy, which is commonly associated with retinal edema and hyperglycemia....
PURPOSE
Endothelin-1 (ET-1) is a potent vasoactive factor implicated in development of diabetic retinopathy, which is commonly associated with retinal edema and hyperglycemia. Although the vasomotor activity of venules contributes to the regulation of tissue fluid homeostasis, responses of human retinal venules to ET-1 under euglycemia and hyperglycemia remain unknown and the ET-1 receptor subtype corresponding to vasomotor function has not been determined. Herein, we addressed these issues by examining the reactivity of isolated human retinal venules to ET-1, and results from porcine retinal venules were compared.
METHODS
Retinal tissues were obtained from patients undergoing enucleation. Human and porcine retinal venules were isolated and pressurized to assess diameter changes in response to ET-1 after exposure to 5 mM control glucose or 25 mM high glucose for 2 hours.
RESULTS
Both human and porcine retinal venules exposed to control glucose developed similar basal tone and constricted comparably to ET-1 in a concentration-dependent manner. ET-1-induced constrictions of human and porcine retinal venules were abolished by ET receptor antagonist BQ123. During high glucose exposure, basal tone of human and porcine retinal venules was unaltered but ET-1-induced vasoconstrictions were enhanced.
CONCLUSIONS
ET-1 elicits comparable constriction of human and porcine retinal venules by activation of ET receptors. In vitro hyperglycemia augments human and porcine retinal venular responses to ET-1.
TRANSLATIONAL RELEVANCE
Similarities in vasoconstriction to ET-1 between human and porcine retinal venules support the latter as an effective model of the human retinal microcirculation to help identify vascular targets for the treatment of retinal complications in patients with diabetes.
Topics: Animals; Constriction; Endothelin-1; Humans; Hyperglycemia; Swine; Vasoconstriction; Venules
PubMed: 32879758
DOI: 10.1167/tvst.9.9.1