View clinical trials related to Vasodilation.
Filter by:The purpose of this project is to examine the impact of increases in brain insulin on sympathetic nervous system activity, as well as peripheral and cerebral blood flow in humans.
The overall goal of this project is to better understand the effect of intermittent hypoxia (IH) on sympathetic neuronal discharge patterns in humans, as well as mechanisms that mediate persistent sympathoexcitation with IH.
This study aims to investigate sex differences in blood pressure control associated with exposure to acute hypoxia (low oxygen), and short term acclimatization to hypoxia at high altitude.
In patients with vasospasm or with negative remodeling, various vasodilator drugs used during coronary angiography can dilate the diameter of the reference vessel to measure the exact vessel size. In particular, nitrates are well known to induce pharmacological vasodilatory effects through vascular smooth muscle relaxation In actual clinical practice, it has been reported that when oral or spray-type nitrate preparations are administered to coronary artery stenosis lesions, the diameter of the reference vessel expands by about 10% compared to the existing vessel diameter. This may enable larger stenting in coronary artery stenosis lesions. Although many patients with vascular stenosis are accompanied by vasospasm and voice remodeling, in actual clinical practice, administration of vasodilators is only used in a small number of patients at the discretion of the surgeon. Nitrate vasodilators administered during coronary angiography are low-dose and short-acting drugs, and although a small number of patients may experience side effects such as short-term lowering of blood pressure, no serious side effects are reported . On this background, this study is to evaluate whether there is a difference in the diameter of the Ultimaster® stent treated with the conventional method compared to the maximally dilated coronary artery, and to evaluate the stability and effectiveness after the procedure.
The CarMA (Carbon Monoxide and Altitude) Study aims to observe the vascular effects of carbon monoxide exposure at low and high altitudes.
Patients with sleep apnea are at increased risk of developing cardiovascular disease - with women at potentially greater risk than men. Contributing mechanisms are not well understood, but may be related to how women respond to low oxygen and, given over 70% of patients with sleep apnea are obese, the impact of obesity. This project seeks to increase our understanding of mechanisms that may contribute to sex differences in the cardiovascular response to low oxygen with the hope that this knowledge will improve the efficacy of current therapies and support the discovery of novel therapeutics.
Adipose tissue is an active endocrine organ producing several hormones with circulatory and metabolic effects. In 1994, the hormone leptin was discovered. The lack of this hormone explained extreme obesity in rare patients and parenteral substitution restored body weight and metabolic disturbances. It was however soon discovered that most humans had too high levels which were related to development of cardiovascular diseases and diabetes. It was hypothesised that leptin induced vessel dysfunction which could explain this association. In this study, we wanted to examine the association between leptin and vessel function by using the venous occlusion plethysmography method. We used three protocols to evaluate this association. First protocol. In ten healthy males, leptin was infused locally in the forearm and forearm blood flow (FBF) was measured. Second protocol. In ten healthy males, leptin or normal saline was infused locally in the forearm and FBF was measured. Concomitantly, four vasodilatators were infused locally in the forearm in a randomised order and the response (blood flow and fibrinolysis) was measured. Third protocol. In eighty-three patients with known coronary artery disease, three vasodilators were infused locally in the forearm in a random order and response (FBF and fibrinolysis) was measured. The response was related to endogenous leptin levels. The two first protocols were performed in Umeå, Sweden whereas the third was performed in Edinburgh, UK, all in 2006.
This study is a pharmacodynamic proof of concept study investigating the physiological effects of systemic infusion of nitrite on coronary blood flow using MRI.
Acutely, during different bouts of passive stretching (PS), blood flow (Q ̇) and shear rate ( ) in the feeding artery of the stretched muscles increases during the first two elongations and then it reduces during the following bouts. This hyperemic response during the first two elongations is mediated by the local release of vasoactive molecules (e.g. nitric oxide, NO). This phenomenon disappears during the following elongations due to the NO and other vasoactive molecule depletion. The relaxation phase between stretching bouts, instead, is always characterized by hyperemia as results of stretch-induced peripheral resistances decrease. Whether chronic PS administration may influence vascular function is still a matter of investigation. The hypothesis is that repetitive PS-induced Q ̇ and changes may be an enough stimulus to provoke increments in NO bioavailability, thus improving vasomotor response.
The purpose of this study is to identify the impact of estradiol (E2) on the mechanisms that regulate vascular endothelial function in peri-menopausal (PERI) women. This study is the first step in understanding factors contributing to endothelial dysfunction in women with advancing reproductive age and in response to E2 administration.