Untitled research work

For further improvement of the technique to form thrombus in hamster cheek pouch, an arteriole with a diameter of 50-80μm was observed under the microscope and was compressed from lateral side up to 1/5 of the internal diameter by glass capillary with tip of 5μm for 10min. Simultaneously electrical stimulation (square-wave direct-current, 20msec in pulse duration, 50μA in pulse strength and 5Hz) was provided for 80sec at the beginning of the compression. When the compression with electrical stimulation was repeated 5 to 7 times every 30-50μm along the arteriolar wall, the thrombus was formed 5-10μm in height and 150-250μm in length. This thrombus was disaggregated neither spontaneously nor by topical application of PGI2. An electronmicrograph of the thrombus showed that endothelial cells were desquamated and degranulated platelets were adherent to the denuded sites. Topical application of ADP induced the formation of large thrombus so that the arteriolar lumen was nearly obstructed. The superimposed parts of thrombus induced by ADP were disaggregated by topical application of PGI2 dose-dependently.