Abstract: | Embryo fibroblasts of hamster, rat, mouse, and were cultured 24 hrs on polyvinylchloride plates with regular relief of grooves with cylindric surfaces in between. Most cells were accumulated on the middle part of spaces between the grooves, their nuclei were elongated and oriented in the direction of grooves. Nuclear elongation was assessed quantitatively by the ratio of long to short nuclear axes. Contact orientation was measured as deviation of the long nuclear axes from the grooves direction. Both contact orientation and elongation considered respectively as "orientation reaction" is maximal and the "form reaction", increased with increasing cylinder curvature (i. e. when the radii diminished from 333 to 61 mcm). Both reactions are well expressed in cultures of the human and (less distinctly) the rat cells. In murine cells, the "orientation reaction" is maximal and the "form reaction" is weak while for the hamster cells the opposite is true. Therefore, both types of reaction seem to be independent characteristics of cells. |