Search results for "Angiotensin II"

Aging modifies receptor expression but not muscular contractile response to angiotensin II in rat jejunum

2022

AbstractThe involvement of renin-angiotensin system in the modulation of gut motility and age-related changes in mRNA expression of angiotensin (Ang II) receptors (ATR) are well accepted. We aimed to characterize, in vitro, the contractile responses induced by Ang II, in jejunum from young (3–6 weeks old) and old rats (≥ 1 year old), to evaluate possible functional differences associated to changes in receptor expression. Mechanical responses to Ang II were examined in vitro as changes in isometric tension. ATR expression was assessed by qRT-PCR. Ang II induced a contractile effect, antagonized by losartan, AT1R antagonist, and increased by PD123319, AT2R antagonist, as well by neural block…

The rxr agonist bexarotene in combination with rosuvastatin inhibits angiotensin-ii induced abdominal aortic aneurysm formation in apoliprotein -e-kn…

2014

Progesterone increases basal 3',5'-cyclic adenosine monophosphate formation and down-regulates the agonist-induced inositol phosphates generation in …

1992

Whether the placenta is a target tissue for estrogens and progesterone, and their putative mechanism of action, is still a controversial question in the literature. The effect of progesterone and estradiol on 3′,5′-cyclic adenosine monophosphate (cAMP) and inositol phosphates generation in human term placenta was investigated. Placental explants were incubated in vitro for up to 48 h in the absence and in the presence of estradiol, progesterone or both steroids (0.1 μmol/l final concentration in all cases), and were stimulated with terbutaline, a β-adrenergic agonist, (0.1 mmol/l) or angiotensin II(1 μmol/l), The cAMP content was measured by a competitive protein binding assay, and the gene…

Telmisartan as metabolic modulator: a new perspective in sports doping?

2011

The World Antidoping Agency (WADA) has introduced some changes in the 2012 prohibited list. Among the leading innovations to the rules are that both 5-aminoimidazole-4-carboxamide-1-[beta]-D-ribofuranoside (peroxisome proliferator�activated receptor-[delta] [PPAR-[delta]]-5' adenosine monophosphate-activated protein kinase [AMPK] agonist) and GW1516 (PPAR-[delta]-agonist) are no longer categorized as gene doping substances in the new 2012 prohibited list but as metabolic modulators in the class �Hormone and metabolic modulators.� This may also be valid for the angotensin II receptor blocker telmisartan. It has recently been shown that telmisartan might induce similar biochemical, biological…

Aldosterone synthase activity in the Y-1 adrenal cell line.

1995

The Y-1 adrenal cell line was shown to produce 20 alpha-dihydroaldosterone from deoxycorticosterone. This compound was identified by GC-MS by comparison with the previously synthesized reference compound. Two other 18-hydroxylated metabolites were identified as 11 beta,18-dihydroxy-20 alpha-dihydroprogesterone from endogenous cholesterol and 18-hydroxy-20 alpha-dihydro-11-dehydrocorticosterone from DOC. The conditions necessary for the synthesis of these compounds are culturing in 20% serum-supplemented medium and repeated incubations with the substrate. The production of 11 beta-hydroxylated steroids and that of 18-oxygenated steroids is stimulated differently by ACTH and angiotensin II su…

AT1 receptors mediate contractile effects of Angiotensin II on mouse colon

2011

Angiotensin II (Ang II) is a potent smooth muscle contractile neurohumoral agonist via interaction with AT1 and AT2 receptors. Although these receptors are well expressed in the gut, very little research has been devoted to analysed the physiological role played by Ang II (and its receptors) in the regulation of gastrointestinal motility. The effects of Ang II on mouse proximal and distal colon contractility, the receptor subtypes involved were investigated in vitro, using the organ bath technique. Longitudinally-oriented segments from mouse proximal and distal colon displayed ongoing contractile activity, characterized by phasic contractions. Ang II induced a concentration-dependent muscul…

Angiotensin II positively modulates the spontaneous contractile activity of mouse and human colon via activation of AT1 receptors.

2012

Objective: Angiotensin II (Ang II) is a potent smooth muscle contractile neurohumoral agonist but has not been much investigated with regard to gastrointestinal motor activity. Ang II effects are mediated by specific receptors, the Ang II type 1 (AT1) and the Ang II type 2 (AT2) receptors, which are well expressed in the gut. In this study we evaluated the effects of Ang II on the contractile activity of longitudinal muscle from mouse and human colon and we analysed the subtype(s) of receptors involved in the observed effects. Methods: Mechanical responses to Ang II, in the absence or in the presence of different drugs, were assessed in vitro in colonic longitudinal muscle from mice and hum…

ANALISI DEI MECCANISMI DI CONTROLLO DELLA MOTILITA’ GASTROINTESTINALE DA PARTE DI ORMONI COINVOLTI NEL BILANCIO IDRICO-SALINO

2014

Focus on clinical practice: angiotensin-converting enzyme 2 and corona virus disease 2019: pathophysiology and clinical implications.

2020

: ACE2 receptor has a broad expression pattern in the cellular membrane and provides a protective action against the development of cardiovascular diseases. Recently, this enzyme has become of extreme interest during the pandemic infection of COVID-19 (coronavirus disease 2019). This virus invades alveolar epithelium and cardiomyocytes using ACE2 as a transmembrane receptor. ACE2 is a counter-regulatory peptide that degrades Ang II into Ang 1-7, thereby attenuating the biological effects of the AT1 receptor. The binding between the spike protein of COVID-19 and the enzyme is crucial for the virus to enter the target cells, but whether an increase in ACE2 activity could facilitate the infect…

Effects of ACE-Inhibitors and Angiotensin Receptor Blockers on Inflammation

2011

The role of inflammation in cardiovascular disease and in hypertensive disease above all, is complex. Several studies confirm that activation of renin-angiotensin-aldosterone system (RAAS), through increase in the production of angiotensin II (Ang II), is closely related to local vascular inflammation. Over the BP lowering effects of anti-hypertensive treatments, several ancillary effects for every class may be found, distinguishing the various drugs from one another. Given the pro-inflammatory effects of Ang II and aldosterone, agents that interfere with the components of RAAS, such as ACE inhibitors, Angiotensin Receptor Blockers (ARBs), and mineralocorticoid receptor antagonists (spirono…