PLATELET ADHESION TO A SPINNING SURFACE
PLATELET ADHESION TO A SPINNING SURFACE
复制标题
血小板对旋转表面的粘附
DOI：
10.1097/00002480-197201000-00087
复制
发表时间：
1972
期刊：
影响因子：
4.2
通讯作者：
E. Leonard
中科院分区：
文献类型：
--
作者：
V. Turitto;E. Leonard
方法用图1所示的旋转盘和旋转室测量血小板粘附率。在盘面(E)上附着有附着有血小板的玻璃盖片。直径12 mm的圆盘用固定螺丝固定在支撑轴(A)上。支撑轴和支撑盘在精密滚珠轴承上旋转，滚珠轴承压入铝轴承壳(B)。轴承座能够在支撑顶部(C)中自由滑动，支撑顶部(C)被强制配合到聚碳酸酯流动室(D)中。在腔体底部的中心加工了直径14 mm、深2 mm的圆形凹槽(F)，使得当轴承座处于最低位置时，盘面位于凹陷的中间。当血液进入腔室时，该凹槽允许盘浸入少量的液体中，防止盘表面存在血-气界面。这种界面被认为对随后的血小板黏附有有害影响(9)。支撑轴由电机驱动，电机通过可互换的同步皮带和滑轮耦合到轴上。电机(GK Heller Co.，2T60-540型)的变速范围为100-4000 rpm，由电子控制器(B和B电机公司，SCR05)调节。马达和控制器可以达到工作速度，也可以在一秒内通过电气制动恢复到零速度。不同大小的滑轮被用来将马达速度降低到每分钟50转。马达速度是用频闪测速仪(Strobotac，General Radio Co.)测定的；然而，只要有可能，就用秒表对旋转计时来检查转速。完整的测量血小板粘附率的实验系统由旋转盘系统、实验动物和连接动物到旋转盘系统的急性植入分流装置组成。这些因素的相互联系如图2所示。在实验之前，一只杂种狗被静脉注射30 mg/kg的戊巴比妥钠麻醉。肝素是一种不影响血小板粘附性的抗凝血剂，给动物注射初始剂量为10,000个单位，然后以每小时5,000个单位的速度持续注射。手术暴露股动脉和静脉或颈动脉和颈静脉两条血管，每条血管在无菌条件下插入直径为1/8“的特氟龙管。将特氟龙套管连接到直径为1/8“的单独的聚乙烯管上，并通过三向旋塞的两部分将聚乙烯管的末端连接起来。这种瓣膜(V1)允许血液在动脉和静脉之间持续流动，或从动脉分流到流动室。然后，瓣膜V1连接到另一块聚乙烯管上，另一个三通旋塞(V2)连接在上面。第二个旋塞的其余两端连接到流室的下部入口和一个30ml注射器。从动脉分流的血液可以被引导到注射器或流动室。V1和V2都可以手动调整，以允许血液从动物进入腔室和从腔室返回到动物。
METHODPlatelet adhesion rates were measured with the rotating disk and chamber shown in Figure 1". A glass cover slip to which platelets adhered was attached to the disk face (E). The disk, 12 mm in diameter, was held on the support shaft (A) by means of a set screw. The support shaft and disk rotated on precision ball bearings which were pressed into an aluminum bearing housing (B). The bearing housing was able to slide freely in the support top (C) which was force-fit into the polycarbonate flow chamber (D). A circular recess (F), 14 mm in diameter and 2 mm deep was machined in the center of the chamber bottom such that the disk face was positioned midway into this depression when the bearing housing was at its lowest position. This recess allowed the disk to be submerged in a small quantity of fluid when blood entered the chamber, preventing the presence of a blood-air interface at the disk surface. Such an interface is believed to have deleterious effects on subsequent platelet adhesion (9). The supporting shaft was driven with an electric motor which was coupled to the shaft by means of inter-changeable timing belts and pulleys. The motor (GK Heller Co., Model 2T60–540) had a variable speed range of 100–4000 rpm and was regulated by an electronic controller (B and B Motor Co., SCR05). The motor and controller were such that operating speed could be reached and also returned to zero speed well within one second using electrical braking. Various sizes of pulleys were used to reduce the motor speed to as low as 50 rpm. Motor speed was determined by use of a stroboscope (Strobotac, General Radio Co.); however, whenever possible the rotational speed was checked by timing the revolutions with a stop watch. The complete experimental system for the measurement of platelet adhesion rates consisted of the rotating disk system, the experimental animal, and an acutely implanted shunt which connected the animal to the rotating disk system. The interconnection of these elements is shown in Figure 2. Prior to an experiment a mongrel dog was anesthetized by intravenous injection of sodium pentobarbital at a dose of 30 mg/Kg. Heparin, an anticoagulant which does not affect platelet adhesion, was administered to the animal with an initial dose of 10,000 units and thereafter continuously at a rate of 5,000 units/hr. Two blood vessels, either the femoral artery and vein or the carotid artery and jugular vein, were surgically exposed and each was cannulated with teflon tubing of 1/8" OD under sterile conditions. The teflon cannulae were connected to separate pieces of polyvinyl tubing of 1/8” ID and the ends of the polyvinyl tubing joined through 2 parts of a 3-way stopcock. This valve (V1) allowed blood to flow continuously between the artery and the vein or to be diverted from the artery into the flow chamber.Valve V1 was then connected to an additional piece of polyvinyl tubing to which another 3-way stopcock (V2) was attached. The remaining 2 ends of the second stopcock were connected to the lower portal of the flow chamber and a 30 ml syringe. Blood diverted from the artery could be directed to either the syringe or the flow chamber. Both V1 and V2 could be manually adjusted to allow both entrance of blood from the animal to the chamber and return of blood from the chamber back to the animal.