The effect of a combined thromboxane receptor- and synthesis-antagonist on platelet, fibrinogen and leucocyte uptake in ePTFE grafts: an experimental study in sheep.
Arterial expanded polytetrafluoroethylene (ePTFE) grafts were interpositioned in the common carotid arteries of 20 adult sheep. This model was used to study the effect of a combined thromboxane receptor- and synthesis-antagonist, Ridogrel (R 68070), on acute graft patency and platelet, fibrinogen and leucocyte uptake. The animals were randomised to treatment (n = 10) or control groups (n = 10). Treatment was given as an intravenous injection with Ridogrel of 8 mg kg body weight-1. The flow in one of the two inserted grafts was restricted to 25 ml min-1. Autologous 111In-labelled platelets, 125I-labelled fibrinogen and 99m-Tc-labelled leucocytes were injected intravenously and the radioactivity over the vessels measured before and after graft insertion using the gamma scintillation technique. After graft insertion the measurements continued for 4 h at two separate points over the proximal and distal anastomosis areas. In the treatment group six out of 10 grafts with restricted flow remained patent compared with nine out of 10 grafts with flow reduction in the control group (N.S.). The median thrombus weights did not differ significantly. There was no difference in the platelet and fibrinogen activities at the proximal anastomosis but distally the animals receiving treatment had a significant reduction during the first 2 h of the experiment. The leucocyte activity in the treatment group compared to the control group did not differ proximally but distally the activity was significantly higher during the last 3 h of the experiment. In the group with unrestricted flow all grafts in both groups remained patent. The thrombus weight was significantly lower in the treatment group compared with the control group.(ABSTRACT TRUNCATED AT 250 WORDS)
Lundell
A
A
Department of Surgery, University of Lund, Malmö General Hospital, Sweden.
Bergqvist
D
D
Leide
S
S
Lindblad
B
B
Ljungberg
J
J
D000818:Animals; D001783:Blood Flow Velocity / Q000187:drug effects; D001807:Blood Vessel Prosthesis; D005340:Fibrinogen / Q000378:metabolism*; D006083:Graft Occlusion, Vascular / Q000097:blood*; D007958:Leukocyte Count / Q000187:drug effects*; D010421:Pentanoic Acids / Q000494:pharmacology*; D010973:Platelet Adhesiveness / Q000187:drug effects*; D011138:Polytetrafluoroethylene; D011725:Pyridines / Q000494:pharmacology*; D011982:Receptors, Prostaglandin / Q000037:antagonists & inhibitors*; D017482:Receptors, Thromboxane; D013928:Thromboxane A2 / Q000037:antagonists & inhibitors*; D013930:Thromboxane-A Synthase / Q000037:antagonists & inhibitors*; D014654:Vascular Patency / Q000187:drug effects
D010421:Pentanoic Acids; D011725:Pyridines; D011982:Receptors, Prostaglandin; D017482:Receptors, Thromboxane; D013928:Thromboxane A2; D005340:Fibrinogen; D011138:Polytetrafluoroethylene; D013930:Thromboxane-A Synthase; C060219:ridogrel