title: The rat isolated colon as a specific assay organ for angiotensin.
abstract: 1. The antagonism of the contractile effects of prostaglandins F(2alpha) and E(2) by polyphloretin phosphate (PPP) was studied on the rat isolated colon.2. PPP (20 mug/ml) was found to reduce the myotropic action of angiotensin I (10 ng/ml) and II (0.3 ng/ml) whereas larger doses of both agents were not influenced.3. It is concluded that when a mixture of antagonists is used, including PPP, the rat isolated colon can be used to assay angiotensin with accuracy and specificity. The addition of 8-L-ala-AT(II) affords a further test of specificity.
mesh_terms: D000804:Angiotensin II / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D000818:Animals; D001285:Atropine / Q000494:pharmacology; D001681:Biological Assay; D003106:Colon / Q000187:drug effects*; D066298:In Vitro Techniques; D008784:Methysergide / Q000494:pharmacology; D010096:Oxprenolol / Q000494:pharmacology; D010646:Phentolamine / Q000494:pharmacology; D010693:Phloretin / Q000494:pharmacology; D011448:Prostaglandin Antagonists; D051381:Rats
chemical_list: D011448:Prostaglandin Antagonists; D000804:Angiotensin II; D010096:Oxprenolol; D001285:Atropine; D010693:Phloretin; D008784:Methysergide; D010646:Phentolamine