This study assesses the receptor subtype (AT1 and AT2) through which angiotensin II (Ang II) mediates contraction in small arteries of young and adult spontaneously hypertensive rats (SHR). Segments of third-order mesenteric arteries ( approximately 200 microm in lumen diameter) were mounted in a pressurized system. Systolic blood pressure and media:lumen ratio of small arteries were significan...

Our study intended to prove whether agonistic autoantibodies to angiotensin II type 1 receptor (AT1-AAs) exist in patients with coronary heart disease (CHD) and affect the human endothelial cell (HEC) by upregulating proinflammatory cytokines expression involved in NF-κB pathway. Antibodies were determined by chronotropic responses of cultured neonatal rat cardiomyocytes coupled with receptor-s...

For several G protein-coupled receptors, amino acids in the seventh transmembrane helix have been implicated in ligand binding and receptor activation. The function of this region in the AT1 angiotensin receptor was further investigated by mutation of two conserved polar residues (Asn294 and Asn295) and the adjacent Phe293 residue. Analysis of the properties of the mutant receptors expressed in...

Regulatory actions of angiotensin II (AngII), which is involved in the pathophysiology of hypertension and also participates in cell proliferation and cell differentiation, are mainly mediated by AngII type 1 (AT1) receptor. Recently, activating mutations of receptors causing hyperfunctioning endocrine diseases have been described in the case of the TSH and LH receptors, implicating that such m...

BACKGROUND Losartan and telmisartan, angiotensin AT1 receptor antagonists, are widely used antihypertensive drugs in patients. It is also known that arterial hypertension is often present in people with epilepsy, therefore, drug interactions between AT1 receptor antagonists and antiepileptic drugs can occur in clinical practice. OBJECTIVES The aim of the current study was to assess the effect...

Angiotensin-converting enzyme inhibitors (ACEi) improve cardiac function and remodeling and prolong survival in patients with heart failure (HF). Blockade of the renin-angiotensin system (RAS) with an angiotensin II type 1 receptor antagonist (AT1-ant) may have a similar beneficial effect. In addition to inhibition of the RAS, ACEi may also act by inhibiting kinin destruction, whereas AT1-ant m...

The dopaminergic and renin-angiotensin systems regulate blood pressure, in part, by affecting sodium transport in renal proximal tubules (RPTs). We have reported that activation of a D1-like receptor decreases AT1 receptor expression in the mouse kidney and in immortalized RPT cells from Wistar-Kyoto (WKY) rats. The current studies were designed to test the hypothesis that activation of the AT1...

The evolving complexity associated with the renin-angiotensin cascade has been the focus of increasingly sophisticated pharmacological experimentation. The identification of at least 2 angiotensin II (Ang II) receptor subtypes led to functional subclassification of their activity. Activation of the type 1 (AT1) receptor is associated with the vasopressive and aldosterone-secreting effects of An...

To assess effects of dietary salt on brain AT1 receptor densities, 4-wk-old Dahl salt-sensitive (Dahl S) and salt-resistant (Dahl R) rats were fed a regular (101 mumol Na/g) or high (1,370 mumol Na/g)-salt diet for 1, 2, or 4 wk. AT1 receptors were assessed by quantitative in vitro autoradiography. AT1 receptor densities did not differ significantly between strains on the regular salt diet. The...

The dopaminergic and renin-angiotensin systems interact to regulate blood pressure. Because this interaction may be perturbed in genetic hypertension, we studied D1 dopamine and AT1 angiotensin receptors in immortalized renal proximal tubule (RPT) and A10 aortic vascular smooth muscle cells. In normotensive Wistar-Kyoto (WKY) rats, the D1-like agonist fenoldopam increased D1 receptors but decre...