In vitro, the renin-secreting juxtaglomerular cells express the calcium-sensing receptor, and its activation with the calcimimetic cinacalcet inhibits renin release. To test whether the activation of calcium-sensing receptor similarly inhibits plasma renin activity (PRA) in vivo, we hypothesized that the calcium-sensing receptor is expressed in juxtaglomerular cells in vivo, and acutely adminis...

The preparation, of an extract of hog blood vessels and organs containing renin activity has been described. The extract hydrolyzes natural or synthetic renin substrate to form a vasopressor material. This reaction could not be distinguished from the hydrolysis of renin substrates by kidney renin. The activation energy, effect of substrate concentration on velocity, inhibition by antirenin, and...

To clarify the role of the renin-angiotensin system in coarctation hypertension, 2-year-old inbred dogs with chronic neonatally induced thoracic aortic coarctation were subjected to 6 days of rigorous salt restriction. The following parameters were then measured: glomerular filtration rate, renal plasma flow, plasma renin activity, plasma renin concentration, renin reactivity, and renin substra...

Renin activity is separated from rabbit plasma by globulin precipitation, dialysis, and DEAE cellulose column chromatography with a Tris chloride buffer system and acid elution, followed by ultrafiltration. The plasma renin extract contains no renin substrate and no angiotensinase activity can be detected after incubation with angiotensin for 200 hr. Incubation with a known concentration of rab...

Peripheral plasma renin activity and aldosterone excretion rates have been measured in normal people during recumbency, recumbent exercise, tilting, and continuous ambulation. Upright posture induces a prompt elevation in peripheral plasma renin activity beginning in 15 minutes and peaking between 60 and 120 minutes. Aldosterone excretion is increased during 120 minutes of upright posture and c...

Hemodynamic and biochemical effects of the new renin inhibitor CGP 38560A (molecular weight 826) were tested in 15 healthy volunteers after a single-blind, randomized, placebo-controlled protocol. At a 2-week interval, groups of five subjects received a 30-minute infusion of either 5% dextrose or CGP 38560A 50, 125, or 250 micrograms/kg. Blood pressure, heart rate, plasma renin activity, active...

1. We examined the effects of various physiological states on systemic and brain renin activities. Activation of the systemic reninangiotensin system (RAS) by renal ischaemia, captopril or continuous renin infusions had no effect on whole brain or pituitary renin activities. Suppression of circulating renin by bilateral nephrectomy or antirenin antibody injection did not influence brain renin. ...

a-Methyldopa significantly lowered mean blood pressure and plasma renin activity in dogs anesthetized with sodium pentobarbital. After unilateral ligation of the right renal vessels and contralateral denervation of the kidney, a-methyldopa significantly lowered mean blood pressure but did not change plasma renin activity. It was concluded that a-methyldopa acutely lowers plasma renin activity v...

1. The major angiotensin I-generating activity of rat brain extracts has a pH optimum different from that of renal renin and is not inhibited by renin specific antibody. 2. Affinity chromatography utilizing renin specific antibody, pepstatin and alpha-casein yielded fractions that resembled renal renin more closely with respect to antibody inhibition and pH optimum as well as an absence of the ...

The present study aims to investigate the regulatory effect of hydrogen sulfide (H(2)S) on cAMP homeostasis and renin degranulation in As4.1 and rat renin-rich kidney cells. It was found in the present study that NaHS at 0.1-10 μM significantly decreased cAMP production in As4.1 cells treated with isoproterenol (a β-adrenoceptor agonist), forskolin (an adenylyl cyclase activator), or 3-isobutyl...