Platelet interaction with vessel wall and collagen in pigs with homozygous von Willebrand's disease associated with abnormal collagen aggregation.
A subgroup of pigs with von Willebrand's disease from the Mayo Clinic stock shows abnormal platelet aggregation in response to collagen [vWD-Homo(-)], in contrast to the normal aggregation responses observed in the main colony of pigs with homozygous vWD [vWD-Homo(+)]. This subgroup has been characterized at Mayo as a storage pool deficiency due to the reduced levels of ADP and Serotonin in the platelet dense granules. In the present studies, an ex-vivo perfusion chamber was utilized to investigate the deposition of 111In-labeled platelets on aortic subendothelium and collagen type I exposed to blood from vWD-Homo(-), vWD-Homo(+) and normal animals. Both non-anticoagulated and heparinized blood were exposed for wall shear rates ranging from 212 sec-1 to 3380 sec-1 and exposure times as long as 30 min. An enhanced decrease in platelet deposition in the vWD-Homo(-) animals was observed compared to vWD-Homo(+) animals. The decrease was observed primarily at the higher shear rates and was more pronounced in the absence of heparin and on the collagenous substrate. Thus, the abnormality in collagen-induced aggregation, which has been characterized as a storage-pool type defect, results in a decreased platelet deposition compared with that produced by severe vWD alone.
Badimon
L
L
Division of Cardiology, Mount Sinai School of Medicine, New York, N.Y.
Badimon
J J
JJ
Galvez
A
A
Turitto
V
V
Fuster
V
V
D000818:Animals; D001808:Blood Vessels / Q000378:metabolism / Q000503:physiopathology*; D003094:Collagen / Q000502:physiology*; D004730:Endothelium, Vascular / Q000502:physiology; D011464:Epoprostenol / Q000378:metabolism; D006493:Heparin / Q000494:pharmacology; D006720:Homozygote; D010477:Perfusion; D010974:Platelet Aggregation; D013552:Swine; D013553:Swine Diseases / Q000097:blood* / Q000235:genetics; D014842:von Willebrand Diseases / Q000097:blood / Q000235:genetics / Q000662:veterinary*
D006493:Heparin; D003094:Collagen; D011464:Epoprostenol