[The formation of motor units in vertebrates (a histophysiological analysis)].
In motor unit anlage successive formation of morphophysiological and biochemical components of system-forming units (histophysiological compartments) occurs. Simultaneously functional differentiation of motor units takes place, based on morphological, biochemical and functional heterogeneity of nervous, muscular and synaptic motor unit components. Intrinsic genetic programmes of main nervous and skeletal muscular tissue differons are the leading ones in early stages of embryogenesis. Morphofunctional base for realization of neurogenic control of skeletal musculature fibres histochemical differentiation forms in muscle anlage. Genetic programmes of two tissues development come to direct (contact) interaction through outer regions of cell membranes: motor neurons participation in skeletal muscular tissue histogenesis, especially on the stage of muscular tubules differentiation into muscular fibres of certain histophysiological type is essential. Most complicated changes are observed in postsynaptic membrane area. This allows to emphasize the development of the symphast nucleo-sarcoplasmic compartment. In further, adaptive changes and morphological manifestations of skeletal muscular tissue genetic programme realization arise in myogenesis with motor neurons role progressively increasing and becoming the predominant one.
Danilov
R K
RK
Radziukevich
T L
TL
D000818:Animals; D002454:Cell Differentiation; D009046:Motor Neurons / Q000502:physiology*; D024510:Muscle Development; D018485:Muscle Fibers, Skeletal / Q000502:physiology; D009132:Muscles / Q000196:embryology / Q000294:innervation; D011984:Sensory Receptor Cells / Q000196:embryology / Q000254:growth & development; D013569:Synapses / Q000502:physiology; D014714:Vertebrates / Q000196:embryology* / Q000254:growth & development*