[Preservation of the bipolar shape and contact orientation by mitotically dividing chick embryo myoblasts in a monolayer culture].

Chick embryo skeletal myoblasts in monolayer cell culture may by spherical during mitosis, as is commonly the case with cells in vitro, or maintain bipolar spindle-form shape throughout all the phases of mitosis. The percentage of spindle-form metaphase myoblast increases from 32% (of al the metaphases), on the 2nd day of culturing, to 80%, on the 5th day. The long axis orientation of mitotic spindle in dividing elongated myoblasts is the same as that of the whole cell. The myoblasts contact orientation (along parallel grooves of artificial substrate or along myotubes) is maintained in bipolar mitotic cells throughout mitosis and persists in daughter cells.