Renin

• ISI Order Code:

  RENIN

• CPT Code:

  84244

Clinical Significance:

Renin is an N-glycosylated member of the aspartyl proteinase family and plays a critical role in the activation of the Renin-Angiotensin-Aldosterone System (RAAS). RAAS activity is involved in the regulation of blood pressure, sodium balance, inflammation, immunity, intracellular redox balance, glucose homeostasis, and the function of adipocytes and hematopoietic progenitor cells. Renin cleavage of Angiotensinogen releases the decapeptide Angiotensin I, which is further cleaved by Angiotensin Converting Enzyme (ACE) and ACE-2 into the bioactive peptides Angiotensin II, Ang1-9, and Ang1-7. Angiotensin II is a potent effector of RAAS activity.

Renin levels can be increased in patients with primary adrenal insufficiency such as Addison’s disease. Levels can also be increased in Bartter syndrome, Gitelman syndrome and pseudohypoaldosteronism type I. Overproduction of renin can also indicate the presence of a reninoma, a tumor of the renal juxtaglomerular cell apparatus that causes hypertension and hypokalemia.

• Reference Range:

  (No Established Range)

Observed values from apparently healthy volunteers

• • Plasma:

    201 – 1852 pg/mL

  • Urine Random:

    up to 96.7 pg/mL

• Procedure:

  Renin is measured by direct ELISA.

• Expected Turnaround Time:

  10 Business Days

Turnaround time is defined as the usual number of days from the date of receipt of a specimen for testing to when the result is released to the ordering facility.

• Report:

  Sample Report

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 Renin 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.

URINE: Collect 5mL of random urine collection or 24-hour collection. Specimen should be frozen and shipped on dry ice. Minimum urine specimen size is 1.0 mL

Special Specimens:

For serum, 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. Hurwitz S, Cohen RJ, Williams GH. Diurnal variation of aldosterone and plasma renin activity: timing relation to melatonin and cortisol and consistency after bed rest. J Appl Physiol (1985). 2004 Apr;96(4):1406-1414. PubMed 14660513

2. Stowasser M, Ahmed AH, Pimenta E, et al. Factors affecting the aldosterone/renin ratio. Horm Metab Res. 2012 Mar;44(3):170-176. PubMed 22147655