Search results for "Angiotensin II"
showing 10 items of 176 documents
Does the renin-angiotensin system also regulate intra-ocular pressure?
2009
The renin-angiotensin-aldosterone system is known to play an essential role in controlling sodium balance and body fluid volumes, and thus blood pressure. In addition to the circulating system which regulates urgent cardiovascular responses, a tissue-localized renin-angiotensin system (RAS) regulates long-term changes in various organs. Many recognized RAS components have also been identified in the human eye. The highly vasoconstrictive angiotensin II (Ang II) is considered the key peptide in the circulatory RAS. However, the ultimate effect of RAS activation at tissue level is more complex, being based not only on the biological activity of Ang II but also on the activities of other produ…
Spectrum of mutations in the renin-angiotensin system genes in autosomal recessive renal tubular dysgenesis
2012
Autosomal recessive renal tubular dysgenesis (RTD) is a severe disorder of renal tubular development characterized by early onset and persistent fetal anuria leading to oligohydramnios and the Potter sequence, associated with skull ossification defects. Early death occurs in most cases from anuria, pulmonary hypoplasia, and refractory arterial hypotension. The disease is linked to mutations in the genes encoding several components of the renin-angiotensin system (RAS): AGT (angiotensinogen), REN (renin), ACE (angiotensin-converting enzyme), and AGTR1 (angiotensin II receptor type 1). Here, we review the series of 54 distinct mutations identified in 48 unrelated families. Most of them are no…
AT1 Receptor Gene Polymorphisms in relation to Postprandial Lipemia
2011
Background. Recent data suggest that the renin-angiotensin system may be involved in triglyceride (TG) metabolism. We explored the effect of the common A1166C and C573T polymorphisms of the angiotensin II type 1 receptor (AT1R) gene on postprandial lipemia.Methods. Eighty-two subjects measured daytime capillary TG, and postprandial lipemia was estimated as incremental area under the TG curve. The C573T and A1166C polymorphisms of the AT1R gene were determined.Results. Postprandial lipemia was significantly higher in homozygous carriers of the 1166-C allele (9.39±8.36 mM*h/L) compared to homozygous carriers of the 1166-A allele (2.02±6.20 mM*h/L) (P<0.05). Postprandial lipemia was similar…
Experiences with Blockade of the Renin System in Human Hypertension Using Converting Enzyme Inhibitor SQ 20,881 and Saralasin
1980
The development of agents which are capable of producing in vivo angiotensin II blockade has provided to investigators and clinicians alike the opportunity to determine and to quantify the extent to which the renin-angiotensin system participates in the maintenance of hypertensive states. High levels of plasma renin activity relative to the state of sodium balance have been documented in patients with malignant, surgically remediable renovascular hypertension and also in some patients with essential hypertension.1 The recent development of the angiotensin II analogue sar1-ala8-angiotensin II (saralasin) provided evidence to support the concept that these elevated renin levels are in fact pa…
Neprilysin inhibition, endorphin dynamics, and early symptomatic improvement in heart failure: a pilot study
2020
Altres ajuts: This work was supported in part by Fundació La Marató de TV3 (201516-10, 201502-30), Societat Catalana de Cardiologia, "la Caixa" Banking Foundation. Altres ajuts: PERIS/SLT002-16-00234 Sacubitril/valsartan is a first-in-class angiotensin receptor-neprilysin inhibitor developed for the treatment of heart failure with reduced ejection fraction. Its benefits are achieved through the inhibition of neprilysin (NEP) and the specific blockade of the angiotensin receptor AT1. The many peptides metabolized by NEP suggest multifaceted potential consequences of its inhibition. We sought to evaluate the short-term changes in serum endorphin (EP) values and their relation with patients' p…
Oxidative stress and endothelial dysfunction: therapeutic implications.
2011
In a previous issue of Annals of Medicine, we presented evidence in support of the concept that an abnormally increased production of reactive oxygen species plays a central role in the genesis and progression of cardiovascular disease. While a number of preclinical lines of evidence support this concept, and despite the results of many studies suggesting a beneficial impact of antioxidant drugs on endothelial function, large clinical trials have failed to demonstrate a benefit of antioxidants on cardiovascular outcomes. Studies exploring the possibility that classical antioxidants such as vitamin C, vitamin E, selenium, or folic acid may improve the prognosis of patients with cardiac disea…
Pentaerithrityl tetranitrate improves angiotensin II induced vascular dysfunction via induction of heme oxygenase-1
2010
The organic nitrate pentaerythritol tetranitrate is devoid of nitrate tolerance, which has been attributed to the induction of the antioxidant enzyme heme oxygenase (HO)-1. With the present study, we tested whether chronic treatment with pentaerythritol tetranitrate can improve angiotensin II–induced vascular oxidative stress and dysfunction. In contrast to isosorbide-5 mononitrate (75 mg/kg per day for 7 days), treatment with pentaerythritol tetranitrate (15 mg/kg per day for 7 days) improved the impaired endothelial and smooth muscle function and normalized vascular and cardiac reactive oxygen species production (mitochondria, NADPH oxidase activity, and uncoupled endothelial NO synthase)…
From Menace to Marvel
2009
Diabetes mellitus is a major risk factor for cardiovascular disease, and its prevalence is suspected to further increase in the coming years in the Western hemisphere and also in countries with emerging economies, like India, China, and Brazil. Together with the increasing prevalence of obesity and metabolic syndrome and the subsequent development of arterial hypertension, the epidemic of adiposity and diabetes mellitus may eat up most of the improvement of cardiovascular outcomes that we have seen within the last decades.1 The risk of atherosclerosis is inversely related to circulating levels of high-density lipoprotein (HDL) cholesterol. Results from the Framingham Study demonstrated that…
Aldosterone biosynthesis induced by ACTH and angiotensin II in newborn rat adrenocortical cells transfected by c-EJ-Ha-ras oncogene
1991
Abstract Adrenocortical cells were obtained by fractionated trypsination of newborn rat adrenal glands and transfected with a plasmid containing the EJ T24 -Ha-ras oncogene. Isolation of adhesive cells led to a proliferative cell line with an overexpression of 21 kDa ras protein. These cells incubated with corticosterone or deoxycorticosterone as the precursor produced a high level of 18-hydroxycorticosterone and aldosterone as identified by gas chromatography- mass spectrometry. ACTH and angiotensin II increased the basal production of aldosterone nineteen-fold and six-fold respectively. Under ACTH stimulation the ratio between aldosterone and 18-hydroxycorticosterone production was 1:3. T…