Plasma Renin Activity ELISA Kit (PRA)

INTENDED USE

Human plasma renin activity ELISA kit is a reliable quantitative procedure for measuring renin activity (PRA, angiotensin I) that is present in plasma. This assay has a sensitivity detection limit of 0.14 pg/ml.

BACKGROUND

Renin which can also be called angiotensinogenase is a 37kDa polypeptide enzyme that is a member of the aspartic acid protease family. The determination of plasma renin activity (PRA) is a vital tool in clinical evaluation of hypertensive patients, where it can assist in diagnosing primary hyperaldosteronism and provide help during the therapy treatment of other forms of hypertension.

The following assay measures human PRA concentrations and the results are expressed in terms of mass of angiotensin I (Ang I) that are generated per volume of human plasma in unit time (ng/mL.h). In contrast to measuring renin concentrations, the determination of PRA is found to be a more accurate indicator of hyperaldosteronism (PHA) because of many reasons for example. Plasma renin concentration assay is unable to ensure sensitivity in low renin states, whilst the assay sensitivity can be enhanced through increasing incubation step during the generation step.

Plasma renin activity is used to express the rate of Ang I formation by action of renin on its substrate angiotensinogen, this makes PRA dependent on concentrations of both renin and angiotensinogen. Whereas the concentrations of angiotensinogen is ignored in renin concentration assays.

CONTENT

All reagents supplied need to be stored at 2 °C – 8 °C, unopened reagents will retain reactivity until expiration date. Do not use reagents beyond this date.

• Wash Buffer Concentrate.
• Substrate Solution: Tetramethylbenzidine (TMB).
• Stopping Solution.
• Standards (A-H): Concentration 0-60 ng/ml.
• Control 1 And Controls 2.
• Assay Buffer.
• Precoated Microplate (2x 96 Wells): Bound by anti-human angiotensin I antigen.
• Streptavidin-Horseradish Peroxidase Conjugate Concentrate.
• Biotin Conjugate: Buffer, protease inhibitors and anti-biotin conjugate.
• PMSF: Phenylmethylsulfonyl fluoride (PMSF).
• Generation Buffer.

SENSITIVITY

The minimum sensitivity detection limit of plasma renin activity (angiotensin I) using current PRA ELISA kit was approximately 0.14 pg/ml. The dynamic range for this assay is 0.2 – 60.0 pg/ml.

ASSAY CHARACTERISTICS

– Sensitivity (Limit Of Detection, LOD): 0.14 ng/ml of Angiotension I
– Specificity (Cross Reactivity): Angiotensin-I (100%), Angiotensin I-9 (0.15%), Angiotensin-II, Angiotensin-III, Angiotensin 1-5 (<0.001%), Renin Substrate Human (0.001%).
– Recovery: 84 – 107%
– Linearity: 82 – 113%
– Intra-Assay Variation: 6.8 – 8.7%
– Inter-Assay Variation: 4.81 – 7.12%
– Expected Normal Values: PRA mean (0.75 ng/ml.h), PRA range (10^th-90^th percentile)(0.06 – 4.69ng/ml.h)

REFERENCES

1. Plasma renin activity (PRA) levels and antihypertensive drug use in a large healthcare system. Am J Hypertens. (2012) 25 (3): 379-88. Sim J.J., et al.
2. Renin angiotensin system blockers may create more risk than reward for sodium-depleted cardiovascular patients with high plasma renin levels. Am J Hypertens. (2013) 26 (6): 727-38. Review. Sealey J.E., et al.
3. Plasma renin testing to guide antihypertensive therapy. Curr Hypertens Rep. (2015) 17 (1): 506. Review. Viera A.J and Furberg C.D.
4. Cost-effectiveness of renin-guided treatment of hypertension. Am J Hypertens. (2013) 26 (11): 1303-10. Smith S.M and Campbell J.D.

ADDITIONAL INFORMATION

• Full Name: Plasma Renin Activity ELISA Kit (PRA)
• Reactivity: Human
• Sample Type: Plasma
• Sensitivity: 0.14 pg/ml

OTHER RELATED ELISA KITS

• Renin (Active) ELISA Kit
• Soluble (Pro)Renin Receptor ELISA Kit
• Angiotensinogen ELISA Kit