Pressor Activity of Angiotensin II-(2-7)-Hexapeptide in Man

抄録

Pressor activity and speed of metabolic degradation of angiotensin II-(2-7)-hexapeptide [ANG-(2-7)] were studied in 5 normal men. When infused iv at a rate of 72nmol/kg·min for 7 min, ANG-(2-7) caused a very slight but statistically significant increase in blood pressure. Average blood pressure increases at 2, 5 and 7min were 5/4, 8/10 and 8/9mmHg, respectively, and the duration of the pressor action after the cessation of the infusion (T) was 5min on the average. The pressor activity and T of this peptide were much less than or shorter than those of angiotensin II-(1-7)-heptapeptide [ANG-(1-7)] iufused previously in the same 5 normal men at a rate of 18 nmol/kg·min indicating that the pressor activity ratio of both the peptides in man is 1:>7.2 which is similar to that of angiotensin II-(2-8)-heptapeptide (angiotensin III) and Ile5-angiotensin II (Ile⁵-ANG II)(1:>5) and that the removal of Nterminal aspartic acid from ANG-(1-7) hastens the speed of metabolic degradation of the peptide as from Ile₅-ANG II.