Portal de Periódicos da CAPES

Action of natural angiotensin II and synthetic analogues on strips of rabbit aorta

1964; American Physiological Society; Volume: 207; Issue: 2 Linguagem: Inglês

10.1152/ajplegacy.1964.207.2.368

2163-5773

O. M. Helmer,

ATP Synthase and ATPases Research

The pressor activity of pure natural asp 1 ileu 5 -angiotensin II, and synthetic asparginyl 1 -val 5 , asp 1 -val 5 , asp 1 -ileu 5 , and ß-asp 1 -val 5 -angiotensin II was determined in a nephrectomized pithed cat. All were of equal potency with the exception of ß-asp 1 -val 5 -angiotensin which was slightly more active. When assayed on the aortic strip asparginyl 1 -val 5 had 25% and ß-asp 1 -val 5 -angiotensin had 75% of the activity of natural angiotensin. The difference in action of the angiotensin peptides can not be explained by their rate of destruction by peptidases. Marked variation in the specificity of different receptors might be responsible. Asparginyl 1 -val 5 -angiotensin II should not be used as a standard in assaying natural angiotensin unless the specificity of the test system has been determined.