Radioisotopic model for investigating thromboembolism in the rabbit.
111Indium (111In)-oxine labeled platelets have been used in a variety of species to assess platelet behavior in vivo. We have shown that 111In-oxine is a suitable label for rabbit platelets and, using a noninvasive technique for the automated, continuous, external imaging of these radiolabeled platelets, we have shown that intravenous adenosine disphosphate (ADP), collagen, platelet activating factor (PAF), and thrombin all elicit dose-related accumulation of platelet-(but not erythrocyte-)associated radioactivity in the thoracic region and a concomitant fall in both the cranial and hindlimb regions of the anesthetized rabbit. Intracarotid (i.c.) ADP, collagen, PAF, and thrombin also produce dose-related increases in platelet-associated radioactivity in the thoracic and decreases in the cranial and hindlimb regions. However, the initial fall in cranial counts induced by i.c. thrombin was followed by a marked increase that was sustained for up to 3 hr. These results suggest this may be a useful model for investigating the mechanisms of platelet activation in the arterial and venous circulations in vivo and may provide a novel model for investigating thromboembolic events in the cerebral circulation.
May
G R
GR
Department of Pharmacology, King's College London, U.K.
Herd
C M
CM
Butler
K D
KD
Page
C P
CP
D000244:Adenosine Diphosphate / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology; D000818:Animals; D001792:Blood Platelets / Q000000981:diagnostic imaging* / Q000187:drug effects; D003094:Collagen / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology; D004912:Erythrocytes / Q000000981:diagnostic imaging / Q000187:drug effects; D005260:Female; D007205:Indium Radioisotopes / Q000008:administration & dosage; D008297:Male; D008954:Models, Biological; D009942:Organometallic Compounds / Q000008:administration & dosage; D015125:Oxyquinoline / Q000008:administration & dosage / Q000031:analogs & derivatives*; D010972:Platelet Activating Factor / Q000494:pharmacology; D011817:Rabbits; D011877:Radionuclide Imaging; D013917:Thrombin / Q000494:pharmacology; D013923:Thromboembolism / Q000209:etiology
D007205:Indium Radioisotopes; D009942:Organometallic Compounds; D010972:Platelet Activating Factor; C032950:indium oxine; D015125:Oxyquinoline; D000244:Adenosine Diphosphate; D003094:Collagen; D013917:Thrombin