Meyers K M, Wardrop K J, Dodds W J, Brassard J
Department of Comparative and Veterinary Anatomy, Pharmacology and Physiology, Pullman, Washington 99164-6520.
Thromb Res. 1990 Jan 1;57(1):97-108. doi: 10.1016/0049-3848(90)90198-l.
Endothelial cells in biopsied blood vessels from von Willebrand factor (vWf)-deficient Doberman pinscher dogs contain immunologically detectable vWf. These dogs and normal dogs were treated with DDAVP (0.6 microgram/kg) and epinephrine (0.5 microgram/kg/min for 30 minutes) and were exercised, using 5 different exercise protocols, (3-4 m/s for 5-40 minutes at 0-5% grade) to determine if treatments reported to increase plasma factor VIII:C/vWf complex in humans would elevate canine plasma vWf. Following the two most strenuous exercise conditions--30 and 40 minutes--plasma von Willebrand factor antigen (vWf:Ag) increased in normal dogs by 30% and 70%, respectively. Factor VIII:C was increased 47% by the most strenuous exercise conditions. The vWf-deficient dogs would not exercise beyond 30 minutes and neither vWf:Ag nor factor VIII:C activity increased. Following DDAVP, plasma vWf:Ag increased in the normal dogs by 47% and factor VIII:C activity was increased by 48%. Factor VIII:C activity increased by 30% in the vWf-deficient dogs, but there was only a slight change in vWf:Ag. Bleeding time decreased in 5 of 6 vWf-deficient dogs. In the normal dogs vWf:Ag increased by 14% after epinephrine infusion, but factor VIII:C activity did not change; neither parameter was altered in the vWf-deficient dogs. While the factor VIII:C/vWf:Ag complex was increased in the normal dog by exercise and DDAVP, the increase is not as pronounced as has been reported for humans. It is not known whether the poor response of the vWf-deficient dog is due to low levels of vWf in their endothelium or to a release defect.
来自血管性血友病因子（vWf）缺乏的杜宾犬活检血管中的内皮细胞含有可通过免疫检测到的vWf。这些犬和正常犬接受了去氨加压素（0.6微克/千克）和肾上腺素（0.5微克/千克/分钟，持续30分钟）治疗，并采用5种不同的运动方案进行运动（速度为3 - 4米/秒，时间为5 - 40分钟，坡度为0 - 5%），以确定据报道可增加人类血浆因子VIII:C/vWf复合物的治疗方法是否会提高犬血浆vWf水平。在两种最剧烈的运动条件下（30分钟和40分钟），正常犬的血浆血管性血友病因子抗原（vWf:Ag）分别增加了30%和70%。最剧烈的运动条件使因子VIII:C增加了47%。vWf缺乏的犬运动时间无法超过30分钟，vWf:Ag和因子VIII:C活性均未增加。给予去氨加压素后，正常犬的血浆vWf:Ag增加了47%，因子VIII:C活性增加了48%。vWf缺乏的犬中因子VIII:C活性增加了30%，但vWf:Ag仅有轻微变化。6只vWf缺乏的犬中有5只出血时间缩短。正常犬在输注肾上腺素后vWf:Ag增加了14%，但因子VIII:C活性未改变；vWf缺乏的犬这两个参数均未改变。虽然正常犬通过运动和去氨加压素使因子VIII:C/vWf:Ag复合物增加，但增加程度不如人类报道的那样显著。尚不清楚vWf缺乏的犬反应不佳是由于其内皮中vWf水平低还是由于释放缺陷。
