Cultivation conditions influencing de novo development of nerve-muscle junctions in vitro.

A variety of cultivation conditions was tested with respect to the formation of nerve-muscle junctions in vitro. The long-term maintenance and survival of innervated muscle fibres was achieved under these conditions: The myoblasts from 11 to 12-day-old chicken embryos were added to a section of the spinal cord with meninges, which was taken from 7 to 9-day-old chicken embryos and cultivated three days in advance in Maximow's assemblies. The myoblasts were prepared from pectoral or leg muscles. The spinal cord sections of the cervical, throacic and lumbar levels were equally successful in inducing the development of nerve-muscle junctions.