Measurement of fibrinopeptide A in human blood

435Citations
Citations of this article
29Readers
Mendeley users who have this article in their library.

Abstract

Since thrombin cleaves fibrinopeptides A (FPA) and B from the NH2 terminal end of the fibrinogen molecule, measurement of fibrinopeptide levels in plasma may provide a direct index of thrombin action. Recently a radioimmunoassay for FPA has been developed, and in this paper, application of this assay to the measurement of FPA levels in clinical blood samples is described. Since fibrinogen cross reacts with antibodies to FPA, dialysis was used to extract the peptide from plasma. In vitro generation of FPA was prevented by removing the fibrinogen from the plasma by precipitation with ethanol before dialysis. The processing technique permitted recovery of 75% of FPA added to blood in vitro. Evidence that the immunoreactivity measured in plasma is due to FPA was provided by the results of experiments in which two antisera to FPA with different specificities showed comparable results and addition of thrombin caused no change in immunoreactivity. In contrast, extracts of streptokinase treated plasma showed a five fold increase in activity when treated with thrombin and markedly different immunoreactivity with the two antisera. Plasma FPA levels in 30 normal men were below 2 ng/ml, with a mean of 0.5 ng/ml. FPA levels in 12 patients with reduced fibrinogen levels or reduced platelet counts or both ranged between 4 and 289 ng/ml. FPA levels in 13 patients with normal or elevated fibrinogen levels, including 6 patients with clinical evidence of venous thrombosis or pulmonary embolism or both, ranged between 5 and 23 ng/ml. FPA and fibrinogen degradation product levels did not correlate, and in several patients, elevated FPA levels were found in the presence of normal fibrinogen degradation product levels. After infusion of FPA containing solutions in four normal individuals, FPA showed a disappearance rate from the plasma consistent with a t1/2 of 3-5 min. Heparin infusions in six patients with venous thrombosis or pulmonary embolism or both and elevated FPA levels were followed by a prompt decline in FPA level at a mean rate equivalent to a 3-5 min t1/2.

Cited by Powered by Scopus

Clot-bound thrombin is protected from inhibition by heparin-antithrombin III but is susceptible to inactivation by antithrombin III-independent inhibitors

1128Citations
N/AReaders
Get full text

Persistent activation of coagulation mechanism in unstable angina and myocardial infarction

593Citations
N/AReaders
Get full text

Treatment with Desmopressin Acetate to Reduce Blood Loss after Cardiac Surgery

422Citations
N/AReaders
Get full text

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Cite

CITATION STYLE

APA

Nossel, H. L., Yudelman, I., Canfield, R. E., Butler, V. P., Spanondis, K., Wilner, G. D., & Qureshi, G. D. (1974). Measurement of fibrinopeptide A in human blood. Journal of Clinical Investigation, 54(1), 43–53. https://doi.org/10.1172/JCI107749

Readers' Seniority

Tooltip

PhD / Post grad / Masters / Doc 11

52%

Researcher 6

29%

Professor / Associate Prof. 3

14%

Lecturer / Post doc 1

5%

Readers' Discipline

Tooltip

Agricultural and Biological Sciences 7

47%

Medicine and Dentistry 3

20%

Biochemistry, Genetics and Molecular Bi... 3

20%

Computer Science 2

13%

Save time finding and organizing research with Mendeley

Sign up for free