What question did this study set out to answer?

To evaluate the specificity and competitive antagonistic properties of 1-Asn-8-Ala-angiotensin II against the vascular effects of angiotensin II in vitro and in vivo.

December 1, 1971Circulation ResearchOpen Access

A Specific Competitive Antagonist of the Vascular Action of Angiotensin II

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To evaluate the specificity and competitive antagonistic properties of 1-Asn-8-Ala-angiotensin II against the vascular effects of angiotensin II in vitro and in vivo.
Assessed contractile responses to angiotensin II, norepinephrine, serotonin, and histamine in isolated rabbit aortic strips to determine pA2 affinity values.
Administered 1-Asn-8-Ala-angiotensin II infusions at 20 to 200 µg/kg·min in pithed rats, conscious normotensive rats, and conscious rats with acute unilateral renal hypertension.
1-Asn-8-Ala-angiotensin II produced a progressive rightward shift in angiotensin II aortic contraction curves with a pA2 of 6.84 ± 0.03, without affecting responses to norepinephrine, serotonin, or histamine.
Infusions at 20 and 60 µg/kg·min shifted angiotensin II pressor curves rightward in pithed rats without altering responses to vasopressin, phenylephrine, or tyramine.
Infusion at 200 µg/kg·min reversed angiotensin II pressor actions and lowered blood pressure in 75% of conscious rats with acute unilateral renal hypertension while eliciting only minor pressor effects in normotensive controls.

Structured PICO

Population

Rabbit aortic strips, pithed rats, and conscious rats (normotensive and with acute unilateral renal hypertension)

Intervention

1-Asn-8-Ala-angiotensin II (in vitro bath concentrations; in vivo infusions at 20, 60, and 200 µg/kg min-1)

Comparator

Angiotensin II alone, and other agonists (norepinephrine, serotonin, histamine, vasopressin, phenylephrine, tyramine)

Outcome

Vascular contraction (in vitro) and pressor effect/blood pressure (in vivo)surrogate

1-Asn-8-Ala-angiotensin II is demonstrated to be a specific competitive antagonist of the vascular action of angiotensin II in both in vitro and in vivo models.

Discussion

No takes yet. Share an insight, caveat, or question.

Implication

No change to clinical hypertension care; leaves open translation of angiotensin II antagonism to human trials.

Cite This Study

Pals et al. (1971) studied this question.

synapsesocial.com/papers/6a71934931a3df824329b42e https://doi.org/10.1161/01.res.29.6.664

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A Specific Competitive Antagonist of the Vascular Action of Angiotensin II

Key Points

Structured PICO

Discussion

Implication

Cite This Study

A Specific Competitive Antagonist of the Vascular Action of Angiotensin II

Key Points

Structured PICO

Discussion

Implication

Cite This Study

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