Angiotensin II

Clinical Significance
Angiotensin II is an eight amino acid peptide formed by Angiotensin Converting Enzyme (ACE) cleavage of Angiotensin I.   Angiotensin II is metabolized further to Angiotensin III.  Angiotensin II release is controlled by Renin, blood pressure, blood volume, sodium balance and by Aldosterone concentration.  Levels of Angiotensin II are increased in many types of hypertension.  Angiotensin II stimulates the release of Anti-Diuretic Hormone, ACTH, Prolactin, Luteinizing Hormone, Oxytocin and Aldosterone.  Angiotensin II increases vasoconstriction and inhibits tubular resorption of sodium, and can increase endothelial cell growth.

Reference Range
10 – 60 pg/ml.

Procedure:
Angiotensin II is measured by direct EIA/ELISA.

Patient Preparation
Patient should be on a normal sodium diet, 110 mEq. sodium.  Patient should be in a recumbent posture for at least 30 minutes prior to collection of specimen.  Diuretics, mineralocorticoids, glucocorticoids, estrogens, oral contraceptives, and ACTH medications and sodium, potassium, and posture all affect Angiotensin levels.

Specimen Collection
3 ml EDTA plasma should be collected and separated as soon as possible.  Freeze plasma immediately after separation.  Minimum specimen size is 1 ml.

Special Specimens
For tumor/tissue and various fluids (i.e. CSF, peritoneal, synovial, etc.), contact the Institute for requirements and special handling.

Shipping Instructions
Ship specimens frozen in dry ice.

References
1. van Hooft IMS, Grobbee DE, Derkx FHM, et al.  Renal Hemodynamics and the Renin-Angiotensin-Aldosterone System in Normotensive Subjects with Hypertensive and Normotensive Patients.  N Engl J Med 324:1305-1311, 1991.

2. Kosunin KJ and Pakarinen A.  Correlations Between Plasma Renin Activity, Angiotensin II, and Aldosterone.  J Clin Endocrinol Metab. 47:665,1978.

CPT Code: 
Angiotensin II 82163