Influence of angiotensin II on the concentration of arterial plasma electrolytes in anaesthetized sheep.
Angiotensin II and I significantly raised potassium and lowered sodium and chloride ion concentrations in arterial plasma, with peak changes occurring in the first 2 min of a 6-min infusion period. The octapeptide increased the arterial K+ level in a dose-dependent manner, but the response showed tachyphylaxis when multiple infusions of 6-min duration were administered after a recovery interval of only 5 min. Raising the arterial blood pressure by 20-33 mmHg with adrenaline and noradrenaline failed to account for the increase in arterial plasma K+ concentration produced by the two peptides. These findings, in particular the rise in K+ concentration, are discussed in relation to possible mechanisms by which angiotensin II affects arteriolar tone.
D000803:Angiotensin I / Q000494:pharmacology; D000804:Angiotensin II / Q000494:pharmacology*; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002118:Calcium / Q000097:blood; D002712:Chlorides / Q000097:blood; D004305:Dose-Response Relationship, Drug; D004573:Electrolytes / Q000097:blood*; D004837:Epinephrine / Q000494:pharmacology; D005260:Female; D009638:Norepinephrine / Q000494:pharmacology; D011188:Potassium / Q000097:blood; D012756:Sheep; D012964:Sodium / Q000097:blood
D002712:Chlorides; D004573:Electrolytes; D000804:Angiotensin II; D000803:Angiotensin I; D012964:Sodium; D011188:Potassium; D002118:Calcium; D009638:Norepinephrine; D004837:Epinephrine