title: Tissue plasminogen activator in human plasma measured by radioimmunoassay.
abstract: A radioimmunoassay (RIA) has been set up using purified human melanoma tissue plasminogen activator and a specific antiserum raised against it. Concentration of antigen in citrated plasma of resting human subjects was found to be 7.1 +/- 1.6 ng/ml (mean +/- S.D.) while the lower limit of sensitivity of the RIA was 2 ng/ml. After venous occlusion or DDAVP infusion the levels of antigen were invariably elevated and a significant increase in the proportion of antigen having fibrin binding properties was observed. Decay studies in vitro and gel filtration of post-stimulus plasma indicated that the RIA detects active and inactive forms of antigen and the possible nature of the inactive antigen is discussed.
authors.affiliation: Scottish National Blood Transfusion Service, Headquarters Laboratory, 2 Forrest Road, Edinburgh, Scotland.
authors.forename: I R
authors.initials: IR
authors.lastname: MacGregor
authors.forename: C V
authors.initials: CV
authors.lastname: Prowse
mesh_terms: D001132:Arm / Q000098:blood supply*; D002850:Chromatography, Gel; D003251:Constriction, Pathologic; D003894:Deamino Arginine Vasopressin / Q000008:administration & dosage*; D005337:Fibrin / Q000378:metabolism; D005342:Fibrinolysis / Q000187:drug effects*; D006490:Hemostatics / Q000008:administration & dosage*; D006801:Humans; D007263:Infusions, Parenteral; D008297:Male; D016491:Peripheral Vascular Diseases / Q000097:blood*; D011863:Radioimmunoassay / Q000592:standards; D015203:Reproducibility of Results; D010959:Tissue Plasminogen Activator / Q000097:blood* / Q000276:immunology
chemical_list: D006490:Hemostatics; D005337:Fibrin; D010959:Tissue Plasminogen Activator; D003894:Deamino Arginine Vasopressin