Plasminogen Activator Inhibitor 1, Activity
Label Mnemonic: PAI1
Epic Lab Code: LAB3869
Downtime Form: A-1a Miscellaneous Request
Commercial Mail-out Laboratory
5231 RCP
356-8593
Specimen(s):
Plasma
Specimen Instructions:
Collect sample between 0800-1200.
Collection Medium:
Light Blue top tube 2.7 mL (Na Citrate)
Minimum:
Preferred Minimum: 1.5 mL platelet poor plasma.
Absolute Minimum: 1.0 mL platelet poor plasma (light blue tube top).
Rejection Criteria:
Serum, hemolyzed specimens; specimens that have been thawed and refrozen
Delivery Instructions:
Deliver to laboratory immediately after collection. Critical frozen.
Turn Around Time:
1-8 days upon receipt at reference laboratory
Reference Range:
By report
Test Limitations:
Plasminogen activator inhibitor-1 (PAI-1) is an inhibitor of tissue plasminogen activator (t-PA), a key enzyme in fibrinolysis. PAI- 1 is synthesized by endothelial cells, platelets, and hepatocytes. Three forms of PAI-1 have been identified. The first form is the active form, while the other two forms are inactive and latent. The main function of PAI-1 in hemostasis is to inhibit t-PA. As PAI-1 levels increase, active levels of t-PA decrease, causing impaired fibrinolytic function. Elevated levels of PAI-1 have been observed in deep-vein thrombosis and myocardial infarction, as well as in normal pregnancy and sepsis. One unit of PAI-1 activity is defined as the amount of PAI-1 that inhibits one international unit of t-PA, as calibrated against the international standard for t-PA. This assay should be used for the quantitative determination of active PAI-1 in human plasma. This may be useful in the diagnosis of thrombotic disease.
Methodology:
Bioimmunoassay
CPT Code:
85415
 
See Additional Information:
Specimens Requiring Immediate Delivery