Search results for "Vascular Resistance"
showing 10 items of 130 documents
Loneliness, Social Isolation, and Cardiovascular Health
2018
Abstract Significance: Social and demographic changes have led to an increased prevalence of loneliness and social isolation in modern society. Recent Advances: Population-based studies have demonstrated that both objective social isolation and the perception of social isolation (loneliness) are correlated with a higher risk of mortality and that both are clearly risk factors for cardiovascular disease (CVD). Lonely individuals have increased peripheral vascular resistance and elevated blood pressure. Socially isolated animals develop more atherosclerosis than those housed in groups. Critical Issues: Molecular mechanisms responsible for the increased cardiovascular risk are poorly understoo…
Effects of nifedipine on renal and cardiovascular responses to neuropeptide y in anesthetized rats
2021
Neuropeptide Y (NPY) acts via multiple receptor subtypes termed Y1, Y2 and Y5. While Y1 receptor-mediated effects, e.g., in the vasculature, are often sensitive to inhibitors of L-type Ca2+ channels such as nifedipine, little is known about the role of such channels in Y5-mediated effects such as diuresis and natriuresis. Therefore, we explored whether nifedipine affects NPY-induced diuresis and natriuresis. After pre-treatment with nifedipine or vehicle, anesthetized rats received infusions or bolus injections of NPY. Infusion NPY (1 µg/kg/min) increased diuresis and natriuresis, and this was attenuated by intraperitoneal injection of nifedipine (3 µg/kg). Concomitant decreases in heart ra…
Non-Invasive Approach for Evaluation of Pulmonary Hypertension Using Extracellular Vesicle-Associated Small Non-Coding RNA.
2019
Extracellular vesicles are released by numerous cell types of the human body under physiological but also under pathophysiological conditions. They are important for cell&ndash
The Effect of Tyramine, Noradrenaline, and Angiotensin on the Blood Pressure in Hypertensive Patients with Aldosteronism and Low Plasma Renin
1970
The reactivity to the pressor action of tyramine, noradrenaline, and angiotensin was determined in 9 patients with hypertension, aldosteronism and low plasma renin concentration (4 patients with solitary adrenal adenomas, 3 patients with nodular adrenal hyperplasia, 2 patients with unknown adrenal status). In 7 patients tests were repeated following unilateral or subtotal adrenalectomy respectively. For comparison, 5 patients with phaeochromocytoma, 10 patients with benign essential hypertension, and 12 normotensive control subjects were studied. — In the hypertensive patients with aldosteronism and low plasma renin, responsiveness to tyramine was significantly reduced. In contrast, pressor…
Effect of obesity on left ventricular function studied by radionuclide angiocardiography
1991
Several studies have shown a significant association of obesity with cardiovascular morbidity and mortality. The present study was carried out to investigate central and systemic haemodynamics in overweight and moderate obese, but otherwise healthy subjects, and in a lean control group to determine whether obesity can influence left ventricular performance per se. In this study an attempt has been made to eliminate misleading factors, such as diabetes, lipid abnormalities and hypertension. A total of 67 subjects, 44 with overweight or moderate obesity and 23 lean healthy subjects, were included. Patients were divided into three groups according to BMI levels and Garrow's criteria as follows…
Circulatory response to volume expansion and transjugular intrahepatic portosystemic shunt in refractory ascites: Relationship with diastolic dysfunc…
2015
Abstract Background Cirrhotic cardiomyopathy may lead to heart failure in stressful circumstances, such as after transjugular intrahepatic portosystemic shunt (TIPS) placement. Aim To examine whether acute volume expansion predicts haemodynamic changes after TIPS and elicits signs of impending heart failure. Methods We prospectively evaluated refractory ascites patients (group A) and compensated cirrhotics (group B), who underwent echocardiography, NT-proBNP measurement, and heart catheterization before and after volume load; group A repeated measurements after TIPS. Results 15 patients in group A (80% male; 54 ± 12.4 years) and 8 in group B (100% male; 56 ± 6.2 years) were enrolled. Echoca…
Optical noninvasive monitoring of skin blood pulsations
2005
Time-resolved detection and analysis of skin backscattered optical signals (remission photoplethysmography or PPG) provide rich information on skin blood volume pulsations and can serve for reliable cardiovascular assessment. Single- and multiple-channel PPG concepts are discussed. Simultaneous data flow from several locations on the human body allows us to study heartbeat pulse-wave propagation in real time and to evaluate vascular resistance. Portable single-, dual-, and four-channel PPG monitoring devices with special software have been designed for real-time data acquisition and processing. The prototype devices have been clinically studied, and their potential for monitoring heart arrh…
Role of Circulating miRNAs as Biomarkers in Idiopathic Pulmonary Arterial Hypertension: Possible Relevance of miR-23a
2015
Idiopathic pulmonary hypertension (IPAH) is a rare disease characterized by a progressive increase in pulmonary vascular resistance leading to heart failure. MicroRNAs (miRNAs) are small noncoding RNAs that control the expression of genes, including some involved in the progression of IPAH, as studied in animals and lung tissue. These molecules circulate freely in the blood and their expression is associated with the progression of different vascular pathologies. Here, we studied the expression profile of circulating miRNAs in 12 well-characterized IPAH patients using microarrays. We found significant changes in 61 miRNAs, of which the expression of miR23a was correlated with the patients’ …
PGC-1α Induction in Pulmonary Arterial Hypertension
2012
Idiopathic Pulmonary arterial hypertension (IPAH) is characterized by the obstructive remodelling of pulmonary arteries, and a progressive elevation in pulmonary arterial pressure (PAP) with subsequent right-sided heart failure and dead. Hypoxia induces the expression of peroxisome proliferator activated receptorγcoactivator-1α(PGC-1α) which regulates oxidative metabolism and mitochondrial biogenesis. We have analysed the expression of PGC-1α, cytochrome C (CYTC), superoxide dismutase (SOD), the total antioxidant status (TAS) and the activity of glutathione peroxidase (GPX) in blood samples of IPAH patients. Expression of PGC-1αwas detected in IPAH patients but not in healthy volunteers. Th…
Sublingual administration of captopril in patients with acute myocardial ischemia.
1991
Summary: To investigate the anti-ischemic capability of the angiotensin-converting enzyme inhibitor captopril, 10 patients with acute myocardial ischemia (angina pectoris >1 h, ST-segment depression ±0.1 mV, no rise in creatine phosphokinase) received 25 mg captopril sublingually after being treated with an intravenous infusion of nitroglycerin (3 mg/h) and heparin (1200 IU/h) for 1 hour. A control group of 10 patients received placebo instead of captopril. Results showed a decrease of the initial ST-segment depression from 0.25±0.04 to 0.2±0.03 mV (p>0.01) with nitroglycerin for the captopril group and from 0.26±0.05 to 0.21±0.05 mV (p>0.01) for the control group. An additional decrease to…