SCANNING ELECTRON-MICROSCOPIC STUDY OF ERYTHROCYTE SHAPES ARTIFICIALLY JETTED THROUGH TUBES AT DIFFERENT PRESSURES BY IN-VITRO CRYOTECHNIQUE FOR ERYTHROCYTES

A new cryotechnique for examining morphological changes of human eryth rocytes at different let pressures was developed in the present study. Human fresh or stored erythrocytes passing through a tube were jetted into precooled isopentane-propane mixture (-193 degrees C), which was named as 'in vitro cryotechnique for erythrocytes'. After the cryotec hnique procedure, the routine freeze-substitution method and subsequen t t-butyl alcohol freeze-drying method were used for preparing the sca nning electron microscopic specimens. At 100 mmHg or higher pressures of letting, lamellar-arranged erythrocytes were observed to have elong ated shapes. The more the letting pressure increased, the fewer discoi d shapes of erythrocytes were observed. This cryofixation technique co uld preserve the morphology of erythrocytes letting from tubes, and pr ovide the three-dimensional image of erythrocyte surfaces, as followed by scanning electron microscopy.