title: The use of proteolytic enzyme inhibitor (Trasylol) in radioreceptor assay of TSH-its application to measuring thyroid stimulating immunoglobulins (TSI) in thyroid diseases.
abstract: In order to estimate thyroid stimulating immunoglobulins (TSI) in serum, a stable, reproducible and sensitive radioreceptor assay (RRA) capable of detecting 100 micromicron of thyroid stimulating hormone (TSH) has been developed using a proteolytic enzyme inhibitor (Trasylol), partially purified human TSH and particulate fractions of human thyroid homogenate. The binding of 125-I-labelled TSH to the crude thyroid membranes was significantly increased from 2-3% to 15-20% in the presence of Trasylol (2000 KIU per tube). Further investigations suggested that Trasylol might inhibit the aggregation of 125I-labelled TSH during incubation with these membranes. With this assay system, the serum immunoglobulins from a great majority of untreated patients with Graves' disease were shown to inhibit the binding of 125I-labelled TSH to those membranes more markedly than those from control subjects. Therefore, this RRA for TSH was considered to provide a sensitive and stable method for detecting TSI.
mesh_terms: D007611:Aprotinin / Q000494:pharmacology*; D001665:Binding Sites / Q000187:drug effects; D002462:Cell Membrane / Q000378:metabolism; D006111:Graves Disease / Q000276:immunology / Q000378:metabolism; D006801:Humans; D007136:Immunoglobulins / Q000032:analysis*; D008928:Mitochondria / Q000378:metabolism; D011480:Protease Inhibitors; D011869:Radioligand Assay; D013959:Thyroid Diseases / Q000276:immunology / Q000378:metabolism*; D013961:Thyroid Gland / Q000378:metabolism*; D013972:Thyrotropin / Q000378:metabolism*; D005719:gamma-Globulins / Q000494:pharmacology
chemical_list: D007136:Immunoglobulins; D011480:Protease Inhibitors; D005719:gamma-Globulins; D013972:Thyrotropin; D007611:Aprotinin