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Axonal transport of norepinephrine (NE) and choline acetyltransferase (ChAc) in the distal portion to the transected and sutured region in the rat sciatic nerve was investigated together with correlations of the contractility of the reinnervated gastrocnemius-plantaris muscle. In the fluorescence histochemical study, the initial delay and the rate of regeneration of noradrenergic fibers were found to be approximately 2 days and 4 mm/day, respectively. In the regenerating nerves, the accumulation of ChAc was about one-half that of normal at 4 weeks and returned to normal at 12 weeks. The amplitude of muscle contraction induced by stimulation of the sciatic nerves was one-half that of normal at 4 weeks and recovered to normal at 12 weeks. The accumulation of NE was still one-fourth that of normal at 12 weeks, and catecholamine fluorescence in the sural artery was still weak, fine, and scattered, compared to that in the artery innervated by the normal sciatic nerve. These results indicate that the function of cholinergic motor fibers correlates with the accumulation of ChAc and that the recovery in amount of transportable NE in the sciatic nerve is much slower than that of the cholinergic component.