[des-Asp1]angiotensin II in the dog: blood levels and effect on aldosterone.
Circulating levels of [des-Asp1]angiotensin II ([des-Asp1]-AII), angiotensin II (AII), and aldosterone were measured in five conscious beagle dogs before and during iv infusion of [des-Asp1]AII at rates of 3, 6, 12, and 24 ng/kg/min. The animals were studied after 4 days on a normal sodium and potassium diet and again after a period of sodium depletion accomplished by iv furosemide (2-5 mg/kg) and 4 days of low sodium diet (2-5 mmol/day). Compared to the normal sodium diet, sodium depletion resulted in increases in the plasma levels of aldosterone from 10 +/- 2 (SE) to 66 (16-116) ng/100 ml of AII from 16 +/- 4 to 52 +/- 13 pmol/liter and of [des-Asp1]AII from 2 +/- 0.7 to 12 +/- 4 nmol/liter. Incremental infusions of [des-Asp1]AII in the sodium replete state resulted in progressive increases in the plasma levels of aldosterone in all dogs. In comparison with a previous study in which dogs were infused with AII, it was apparent that [des-Asp1]AII was equally or slightly more potent in stimulating aldosterone and had a higher metabolic clearance rate than AII. [des-Asp1]AII stimulated aldosterone in four of the five sodium-depleted dogs but no steepening of the [des-Asp1]AII/aldosterone dose-response curves was apparent. These results do not support the hypothesis that circulating [des-Asp1]AII mediates the effect of AII on aldosterone in the dog.
D000450:Aldosterone / Q000097:blood*; D000804:Angiotensin II / Q000031:analogs & derivatives* / Q000097:blood; D000805:Angiotensin III / Q000097:blood* / Q000494:pharmacology; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D004039:Diet, Sodium-Restricted; D004285:Dogs; D005665:Furosemide / Q000494:pharmacology; D008297:Male; D011188:Potassium; D012964:Sodium / Q000097:blood
D000804:Angiotensin II; D000805:Angiotensin III; D000450:Aldosterone; D005665:Furosemide; D012964:Sodium; D011188:Potassium