MICROSCOPY AND MANIPULATION OF CELLS IN ELASTIC CAPILLARIES

Microscopy in round glass capillaries does not give an acceptable imag e of the contents because of strong distortions. Square, and generally right-angle, capillaries provide a higher quality image, but no acces s to the cell. Capillaries of elastomers combine good optical quality with access to the cell, and a great variety of manipulation through t he capillary and by the capillary. Three properties are most important for capillary cell manipulation: (1) extensibility or elongation limi t of a capillary, reaching 7-8 times and more, with latex, polyurethan e and silicone; (2) transparency, which is sufficiently high for trans mitted light microscopy in thin layers of elastomers; and (3) hardness , low in elastic materials, permits puncturing the capillary wall to r each the cell. Capillaries, owing to their softness and flexibility, m ay be flattened easily to improve observation. Cell manipulations, the n, are possible with extensible capillaries: (1) elongation of the cel l into a thin strand 7-8 times longer than cell diameter, thus separat ing cell structures; (2) excision of cell parts; (3) precise microscop y of the nucleus and organelles not masked by the cytoplasm; (4) micro injection; and (5) stimulation of contraction and relaxation of the ce ll.