title: In vivo behaviour of vesicular urokinase.
abstract: Thromboembolic diseases including deep vein thrombus (DVT) are major causes of morbidity and mortality. Detection of DVT in low extremities is difficult. There are some accepted imaging techniques in clinic but most of them have several disadvantages limiting their effective use. Because of this, researchers are still performed to develop a rapid, specific means of detecting and/or imaging venous thrombi-based on the changing composition of the thrombus. Urokinase, fibrinolytic enzyme isolated form human urine, is a direct activator of plasminogen. In thrombus formation, plasminogen seems to be trapped in or absorbed onto fibrin matrix thus leading to a localised concentration of plasminogen. This suggests that radiolabelled urokinase would be a suitable compound for the detection of thrombi. The most important disadvantage of this enzyme is short plasma half life. To overcome this problem, it was decided to encapsulate the enzyme in drug delivery systems such as liposomes, niosomes or sphingosomes. In this study, we prepared, characterized and monitored the biodistribution of three types of vesicular systems containing urokinase. All types of prepared vesicles show in vitro an acceptable encapsulation, stability and release profile. Thrombus uptake was increased by encapsulation of urokinase into vesicles.
authors.affiliation: Department of Radiopharmacy, Faculty of Pharmacy, Hacettepe University, 06100 Ankara, Turkey.
authors.forename: Suna
authors.initials: S
authors.lastname: Erdoğan
authors.forename: A Yekta
authors.initials: AY
authors.lastname: Ozer
authors.forename: Hasan
authors.initials: H
authors.lastname: Bilgili
mesh_terms: D000818:Animals; D016503:Drug Delivery Systems; D005260:Female; D008081:Liposomes; D011817:Rabbits; D014018:Tissue Distribution; D014568:Urokinase-Type Plasminogen Activator / Q000008:administration & dosage* / Q000493:pharmacokinetics
chemical_list: D008081:Liposomes; D014568:Urokinase-Type Plasminogen Activator