[Modern concepts of the structure and function of muscle spindles in mammals].

The review provides data on the pre- and postnatal ontogenesis of muscle spindles. I demonstrated the roles of various sections of the nervous system in the mechanism of development and differentiation of the intrafusal muscle fibres. It provides data on the structure, dynamic and static nuclear bag muscle and nuclear chain fibres, their motoric and sensory innervations. It discussed the functional characteristics of responses from the primary and secondary endings to various mechanical stimulations. The paper discusses the results describing potentials (local and distributing) of intrafusal fibres of all types. It also describes the role of fusimotor innervation in regulation of the sensory activity of muscle spindles.