Search results for "Renin"
showing 10 items of 179 documents
Renin-angiotensin system gene polymorphisms: relationship with blood pressure and microalbuminuria in telmisartan-treated hypertensive patients.
2004
This study analyzed the relationship between four renin–angiotensin system (RAS) gene polymorphisms and the response to blood pressure lowering and development of microalbuminuria in 206 patients with essential hypertension treated once daily for 12 months with telmisartan 80 mg. Seated cuff blood pressure and urinary albumin excretion (UAE) were measured throughout the study. Patients were screened for the presence of the A-6G variant of the angiotensinogen gene, angiotensin-converting enzyme insertion/deletion polymorphism, and the A1166C and C573T polymorphisms of the angiotensin II type 1 receptor gene. No significant association was found between the presence of any gene polymorphism a…
Drug induced variations of the renin-angiotensin-aldosterone system in rats. II. Antihypertensives
1977
Summary Groups of male rats were treated with antihypertensive drugs (alpha-methyl-dopa, clonidine, propranolol, reserpine, diazoxide) which were administered under conditions causing the onset of high plasma renin activity (PRA) and high plasma and urine aldosterone levels, i.e. together with distilled water load (5% of body weight). Alpha-methyl-dopa and propranolol, which fail to significantly alter PRA and plasma aldosterone levels when administered without distilled water load, cause a marked decrease of plasma and urine aldosterone levels and of PRA when administered together with distilled water load, while diazoxide, and reserpine cause a marked increase of these values. Clonidine c…
Novel antihypertensive hexa- and heptapeptides with ACE-inhibiting properties: From the in vitro ACE assay to the spontaneously hypertensive rat
2011
Bioactive ACE inhibiting peptides are gaining interest in hypertension treatment. We have designed and screened six synthetic heptapeptides (PACEI48 to PACEI53) based on two hexapeptide leads (PACEI32 and PACEI34) to improve ACE inhibitory properties and assess their antihypertensive effects. ACE activity was assayed in vitro and ex vivo. Selected peptides were administered to spontaneously hypertensive rats (SHRs) and normotensive Wistar-Kyoto (WKY) rats. In vitro cytotoxicity was assessed with the MTT reduction test. The six heptapeptides at low micromolar concentration produced different degrees of in vitro inhibition of ACE activity using the synthetic substrate HHL or the natural subst…
Angiotensin II contractile effects in mouse colon: role for pre- and post-junctional AT1A receptors
2013
Aim This study investigates whether a local renin–angiotensin system (RAS) exists in mouse colon and whether angiotensin II (Ang II) may play a role in the regulation of the contractile activity. Methods Isometric recordings were performed in vitro on the longitudinal muscle of mouse proximal and distal colon. Transcripts encoding for RAS components were investigated by RT-PCR. Results Ang II caused, in both preparations, a concentration-dependent contractile effect, antagonized by losartan, AT1 receptor antagonist, but not by PD123319, AT2 receptor antagonist. The combination of losartan plus PD123319 caused no change on the Ang II-induced contraction than losartan alone. Tetrodotoxin, neu…
Transmural distribution of biochemical markers of total protein and collagen synthesis, myocardial contraction speed and capillary density in the rat…
1988
The effect of angiotensin II-induced hypertension on selected biochemical parameters was studied in Sprague-Dawley rats. Angiotensin II infusion at rates of 41.7 micrograms h-1 kg-1 and 12.5 micrograms h-1 kg-1 for 2, 5, 10 and 15 days elevated the systolic blood pressure from 143 +/- 7 mmHg to 215-230 mmHg (P less than 0.001) and 185-195 mmHg (P less than 0.001), respectively. The left ventricular weight/body weight ratio increased 10-14% (P less than 0.05) and 23-32% (P less than 0.001) after 2-15 days in rats treated at the lower and higher infusion rates, respectively. Prolyl 4-hydroxylase (PH) activity, a marker of collagen synthesis, was evenly distributed in the left ventricle. PH ac…
Drug-induced variations of the renin-angiotensin-aldosterone system in rats. I. Diuretics.
1977
Summary Groups of 10 rats were treated with diuretics (furosemide, hydrochlorotiazide, spironolactone, triamterene) under conditions of high or low plasma renin activity (PRA) brought about by administering distilled water or saline load, respectively. PRA, plasma aldosterone levels, urine aldosterone concentration as well as diuresis and Na+ and K+ excretion were
Left ventricular hypertrophy and geometry in hypertensive patients with chronic kidney disease.
2009
To evaluate the prevalence of left ventricular hypertrophy (LVH) and left ventricular geometry in a group of 293 hypertensive patients with stage 2-5 chronic kidney disease (CKD), compared with 289 essential hypertensive patients with normal renal function.All patients underwent echocardiographic examination. Patients on stage 1 CKD, dialysis treatment, or with cardiovascular diseases were excluded.LVH was observed in 47.1% of patients with CKD and in 31.14% of essential hypertensive patients (P0.0001). We found increasingly higher left ventricular diameters, thicknesses, and mass from stage 2 to 5 CKD. Distribution of concentric and eccentric LVH was not different between the two groups. H…
Decreased kynurenine pathway potentiate resilience to social defeat effect on cocaine rewa
2021
The kynurenine (KYN) pathway of tryptophan (TRP) degradation is activated by stress and inflammatory factors. It is now well established that social stress induces the activation of the immune system, with central inflammation and KYN metabolism being two of the main factors linking stress with depression. The aim of the present study was to evaluate the long-lasting changes in the KYN pathway induced by social defeat (SD) associated with the resilience or susceptibility to an increase in the conditioned rewarding effects of cocaine. Mice were exposed to repeated SD and 3 weeks later, a conditioned place preference (CPP) induced by a subthreshold dose of cocaine (1.5 mg/kg) was developed. K…
Activation of angiotensin II type 1 receptors and contractile activity in human sigmoid colon in vitro.
2015
We propose and validate a non-invasive method that enables accurate detection of the discharge times of a relatively large number of motor units during excitatory and inhibitory reflex stimulations. HDsEMG and intramuscular EMG (iEMG) were recorded from the tibialis anterior muscle during ankle dorsiflexions performed at 5%, 10%, and 20% of the maximum voluntary contraction (MVC) force, in 9 healthy subjects. The tibial nerve (inhibitory reflex) and the peroneal nerve (excitatory reflex) were stimulated with constant current stimuli. In total, 416 motor units were identified from the automatic decomposition of the HDsEMG. The iEMG was decomposed using a state-of-the-art decomposition tool a…
Plasma Renin Concentration is Associated With Hemodynamic Deficiency and Adverse Renal Outcome in Septic Shock.
2019
International audience; Background: In septic shock, both systemic vasodilatation and glomerular arteriole dilatation are responsible for the drop in glomerular filtration observed in early acute kidney injury. Angiotensin II has been showed to act on both mechanisms. Our objective was to evaluate the impact of renin angiotensin system activation, on hemodynamic deficiency and renal outcome in patient with septic shock and to assess whether urinary sodium could be a reliable test for high plasma renin concentration screening.Methods: This was a prospective and observational study. Inclusion criteria were 1) early septic shock (first episode) 2) dose of norepinephrine ≥ 0.25 μg/kg/min 3) bef…