Quantitative Versuche über das Fadenziehvermögen von Fibroblasten

Summary

A modified technique for measuring the length of threads pulled out from fibroblasts grown in vitro has been given which is applicable to an exact determination of the ability of Fadenziehen (thread-drawing). Measurements have been done, for that purpose, also of the thickness of the fibroblasts layer by means of an interference microscope, of the flow elasticity by means of Scott Blair's menstroscope (oestroscope), and of the birefringence by means of two very accurate methods.

The lengths of the threads pulled out show a maximum amount at middle values of speeds of pulling out, of viscosity (estimated by the behaviour towards salt solutions with different cations), and of flow elasticity. The values increase in proportion with the depth of diping, with the luminas of the capillaries, and with increase of leptonic orientation or birefringence.

All the results are to interprete with differences between the distinct speeds of pulling out the threads of protoplasm and of its flowing after and back. The results are, finally, discussed particularly in relation to the possible manner which the so-called Fadenziehen of protoplasm depends on. In as much as the investigated processes are conducted by viscosity and flow elasticity, but perhaps also by surface tension, adhesion, interleptonic bonds of protoplasmic material &c., thecausa efficiens of the ability results from a distinct co-operation of many factors mostly of the molecular range.