THE RESPONSE OF FAST AND SLOW NUCLEAR BAG FIBRES AND NUCLEAR CHAIN FIBRES IN ISOLATED CAT MUSCLE SPINDLES TO FUSIMOTOR STIMULATION, AND THE EFFECT OF INTRAFUSAL CONTRACTION ON THE SENSORY ENDINGS

Abstract

The mechanical behavior of intrafusal muscle fibers during fusimotor stimulation and passive stretch was observed directly in muscle spindles isolated from the cat tenuissimus muscle. Three functional types of mammalian intrafusal muscle fibers, i.e., slow nuclear bag fiber, fast nuclear bag fiber and nuclear chain fiber, were studied.