Search results for "vasodilation"
showing 10 items of 228 documents
Effects of sildenafil on human penile blood vessels.
2000
Abstract Objectives. To investigate the effects of sildenafil on human penile blood vessels and evaluate the interaction of sildenafil with neurogenic-mediated responses. Sildenafil is currently used in the treatment of erectile dysfunction. Methods. Penile dorsal arteries and deep dorsal veins were obtained from 14 multiorgan donors. Vascular rings were suspended in organ bath chambers, and the isometric tension was recorded. We then studied the effects of sildenafil on precontracted vessels and the neurogenic (noradrenergic and nitrergic) responses. Results. Sildenafil (10 −9 to 3 × 10 −6 M) caused concentration-dependent relaxation and amplified the relaxation induced by sodium nitroprus…
Effects of endurance exercise on serum concentration of calcitonin gene-related peptide (CGRP): A potential link between exercise intensity and heada…
2020
Abstract Background Calcitonin gene-related peptide (CGRP) is a powerful neuropeptide that is strongly involved in headache pain pathogenesis by triggering vasodilation, mast cell degranulation and neurogenic inflammation. This evidence has prompted us to investigate the acute influence of endurance exercise on CGRP concentration in blood. Methods The study population consisted of 48 male amateur runners, who ran a half-marathon distance at 75%–85% of maximal oxygen uptake. Blood was drawn before the run (pre-run) and immediately after each runner ended his trial (post-run). The serum concentration of CGRP was measured with a commercial enzyme-linked immunosorbent assay (ELISA) technique. R…
Inability of HDL from abdominally obese subjects to counteract the inhibitory effect of oxidized LDL on vasorelaxation.
2007
Abdominal obesity is associated with a decreased plasma concentration of HDL cholesterol and with qualitative modifications of HDL, such as triglyceride enrichment. Our aim was to determine, in isolated aorta rings, whether HDL from obese subjects can counteract the inhibitory effect of oxidized low density lipoprotein (OxLDL) on endothelium-dependent vasodilation as efficiently as HDL from normolipidemic, lean subjects. Plasma triglycerides were 74% higher (P < 0.005) in obese subjects compared with controls, and apolipoprotein A-I (apoA-I) and HDL cholesterol concentrations were 12% and 17% lower (P < 0.05), respectively. HDL from control subjects significantly reduced the inhibitory effe…
Dose-dependent effects of decaffeinated coffee on endothelial function in healthy subjects
2009
ackground/Objectives: Coffee is known to contain antioxidant substances whose effects may be blunted because of caffeine that may unfavorably affect the cardiovascular system. This study was designed to investigate the acute dose-dependent effects of decaffeinated coffee (DC) on endothelial function measured by the brachial artery flow-mediated dilation (FMD). Subjects/Methods: A total of 15 (8 men and 7 women) healthy nonobese subjects underwent a single-blind, crossover study. Subjects ingested one and two cups of decaffeinated Italian espresso coffee in random order at 5- to 7-day intervals. Results: In the hour following the ingestion of two cups of DC, FMD increased (mean±s.e.m.): 0 mi…
Erectile dysfunction is associated with low total serum testosterone levels and impaired flow-mediated vasodilation in intermediate risk men accordin…
2015
Background: The role erectile dysfunction (ED) coupled with low testosterone levels as early markers of atherosclerosis is not well understood. Objectives: To analyze the relationship between serum testosterone levels with both ED and brachial artery flow-mediated vasodilation (FMD), in a primary prevention sample of men. Methods: We enrolled 802 asymptomatic, intermediate CV risk patients, according to the Framingham Risk Score, aged 40e80 years, who underwent the ultrasound examination of FMD, the evaluation of ED and the assessment of total serum testosterone levels. Results: Testosterone levels correlated both with FMD (r ¼ 0.85; p < 0.0001) and IIEF-5 score (rs ¼ 0.65; p < 0.0001…
Noninvasive peripheral vascular function and atrial fibrillation in the general population.
2019
Background Arterial stiffness is a strong predictor of atrial fibrillation in the community. Whether noninvasively measured conduit artery function and peripheral vascular reactivity are related to atrial fibrillation remains unknown. Methods and results In 15 010 individuals of the population-based Gutenberg Health Study, mean age 55 ± 11 years, 50.5% men, we determined noninvasive vascular function by flow-mediated dilation (FMD) and peripheral arterial tonometry (PAT) in relation to manifest atrial fibrillation (N = 466). Patients with atrial fibrillation exhibited a higher mean brachial artery diameter [4.81 mm (4.17, 5.33) in atrial fibrillation vs. 4.31 mm (3.67, 4.93)] and baseline p…
Angiotensin converting enzyme has an inhibitory role in CGRP metabolism in human skin
2005
The neutral endopeptidase (NEP) is important for calcitonin gene related peptide (CGRP) degradation, while the role of angiotensin converting enzyme (ACE) remains unclear. By using dermal microdialysis we explored the effect of phosphoramidon (NEP blocker), captopril (ACE blocker) and a mixture of both drugs on the intensity of electrically-induced CGRP-mediated neurogenic flare. The results reveal that phosphoramidon elevated flare intensity, but that this was not further increased by adding captopril. In contrast, neurogenic flare was decreased when the drug mixture was applied in compared to NEP only. Electrically released CGRP levels could be measured directly in perfusates containing p…
Intra- and extracerebral blood flow changes and flushing after intravenous injection of human corticotropin-releasing hormone
1994
To study facial flush after systemic administration of human corticotropin-releasing hormone (hCRH) we injected 100 micrograms hCRH intravenously to ten healthy young men. The increase in facial temperature was measured by infrared camera. A significant increase in facial temperature of 1.39 degrees C +/- 0.3 was found within 7 min in all patients, which lasted up to 60 min, although facial flushing was visible in only 50% (5/10) of the probands. In a second experiment 100 micrograms hCRH was then administered to seven other healthy young men. Intra- and extracerebral blood flow velocity changes in the medial cerebral artery (MCA) and external carotid artery (ECA) were measured after hCRH a…
Electrically stimulated axon reflexes are diminished in diabetic small fiber neuropathies.
2004
Axon reflex mediated flare depends on the density and the function of cutaneous C-fibers and may be impaired in diabetic neuropathy. We induced neurogenic axon reflex flare by intracutaneous electrical stimulation and analyzed size and intensity of the flare on the dorsum of the foot and ventral thigh with laser Doppler imaging (LDI). We investigated 12 diabetic subjects with small fiber neuropathies (SFNs), 5 diabetic subjects without neuropathy (NO-Ns), and 14 healthy control subjects. Five of the normal subjects were reassessed after 12 months. In comparing patients with SFN to control subjects, we found that SFN flare size but not the intensity of vasodilation (flux) was reduced on the …
Coadministration of atorvastatin prevents nitroglycerin-induced endothelial dysfunction and nitrate tolerance in healthy humans.
2010
Objectives We aimed to assess whether concurrent administration of atorvastatin would modify the development of tolerance and endothelial dysfunction associated with sustained nitroglycerin (GTN) therapy in humans. Background Animal studies have demonstrated that administration of 3-hydroxy-3 methylglutaryl coenzyme A reductase inhibitors can protect against GTN-induced endothelial dysfunction and tolerance, likely through an antioxidant mechanism. Methods Thirty-six healthy male volunteers were randomized to receive continuous transdermal GTN (0.6 mg/h) and placebo, atorvastatin (80 mg/day) alone, or continuous transdermal GTN (0.6 mg/h) with concurrent atorvastatin (80 mg/day), all for 7 …