title: Hemostatic factors in rabbit limb lymph: relationship to mechanisms regulating extravascular coagulation.
abstract: Mechanisms regulating extravascular coagulation in interstitial fluids of peripheral tissues are poorly understood, since measurements of hemostatic factors in these fluids are unavailable. Because lymph from a body region reflects the composition of its interstitial fluid, we measured hemostatic factors in limb lymph of rabbits both as activity and as antigen. Mean lymph-to-plasma activity ratios were the following: fibrinogen, 0.28; prothrombin, 0.26; factor X, 0.27; factor VII, 0.17; and factors V and VIII, 0.08. All lymph fibrinogen was clottable; fibrin degradation products were absent. Lymph von Willebrand factor antigen was < 10% of plasma antigen and consisted primarily of lower molecular weight multimers. Mean lymph-to-plasma activity ratio for antithrombin was 0.38 and for tissue factor pathway inhibitor the ratio was 0.40. Low levels of antithrombin-factor Xa were measurable in lymph. The data are compatible with a basal factor VIIa-tissue factor-catalyzed extravascular activation of factor X that is prevented from progressing to generation of fibrin in limb interstitial fluid and lymph by low levels of factor VIII and factor V and by the inhibitory activity of antithrombin and tissue factor pathway inhibitor.
authors.affiliation: Department of Pathology, University of California, San Diego, La Jolla 92093-0612, USA.
authors.forename: D T
authors.initials: DT
authors.lastname: Le
authors.forename: P
authors.initials: P
authors.lastname: Borgs
authors.forename: T W
authors.initials: TW
authors.lastname: Toneff
authors.forename: M H
authors.initials: MH
authors.lastname: Witte
authors.forename: S I
authors.initials: SI
authors.lastname: Rapaport
mesh_terms: D000818:Animals; D000990:Antithrombin III / Q000032:analysis; D001777:Blood Coagulation; D001779:Blood Coagulation Factors / Q000032:analysis*; D015153:Blotting, Western; D005121:Extremities / Q000098:blood supply*; D005167:Factor VII / Q000032:analysis; D005170:Factor X / Q000032:analysis; D005172:Factor XI / Q000032:analysis; D005260:Female; D006487:Hemostasis; D008196:Lymph / Q000737:chemistry*; D008208:Lymphatic System / Q000502:physiology*; D008297:Male; D011516:Prothrombin / Q000032:analysis; D011817:Rabbits; D013925:Thromboplastin / Q000032:analysis
chemical_list: D001779:Blood Coagulation Factors; D000990:Antithrombin III; D005167:Factor VII; D011516:Prothrombin; D005170:Factor X; D005172:Factor XI; D013925:Thromboplastin