| Nerve injury is very common and because of the poor prognosis and high functional impairment rate, they are highlighted by doctors. Restoration of function of injured nerve is still a hard question for medical society today. Poor regeneration ability of nerve tissue, environment and time limitation of nerve regrowth, together with the irreversible atrophy and fibrosis of the target organ like muscles contribute to poor recovery of function after nerve injury. In order to solve this problem, a lot of basic and clinical research has been carried out, but the result keeps the same basically in spite of the progress in some aspect. Recently the nutritional and protective effect of FK506 on nerve tissue has drawn more and more emphasis from researchers. In this study, begining with the factors that affect the restoration of fuction of injured spinal cord and peripheral nerve, we dicussed the effect of FK506 on regrowth of injured peripheral nerve, the neuroprotective effects of FK506 on injured spinal cord and its potential to improve regrowth of the injured spinal cord, and finally we disccused the effect of Bambuterol and Danggui on preventing atrophy of denerved muscle.Part One : Experimental Study of FK506 on Axonal Regeneration in the Rat Sciatic Nerve.Objective: Peripheral nerve injury is very common in clinical work. A series studies have proven that the immunosuppressant FK506 can expedite nerve growth by ill-understood mechanisms. In this study, we aim at applying FK506 to probe into its efficacy in expediting nerve regeneration and the method of administration to look forward to searching for a new way in the treatment of peripheral nerve injury.Methods: Sixty adult male SD rats received a neurotomy to bilateral sciatic nerve and subsequently reconnected with silicon tube. The regeneration chambers was infused with either normal saline (group A and group B) or 1μg/ml FK506 (group C). The rats of group B also received daily s.c. injection of FK506 (1mg/kg) at the back of the neck for 14 days. Observe the general condition of the rats, local immunoreaction and the histological change in light or electron microscope at designate time after neurotomy. Nerve conduction and regeneration were evaluated by the weight of gastrocnemius muscles, electrophysiology and morphometric analysis.Results: Rats of group B showed less motion, malnutrition and failed to gain weight. The extent of local lymphocytes infiltration in group B&C was lighter than that in group A at POD 24hr, 72hr and 1week. Axons and myelin sheath distal to the injured site showed degenerated and collapsed at POD 2w. There is no significance among the regenerative extent of nerve at POD 4w. At POD 6w, morphometric analysis confirmed that the number of myelinated fiber, myelin width and axon diameter were maximally increased in the B group. Muscle weight of group B&C were larger than that of group A. MNCV and conductive time in group B are better than that in group A, and showed no significance with group C at POD 6w. CMAP amplitude in group B was better than that in group A&C.Conclusion: (1) Systemic administration of FK506(1mg/kg) possesses neuroprotective and neurotrophic function, which can facilitate nerve regeneration and promote functional recovery.(2) Local administration of FK506(1μg/ml) possesses some extent of neuroprotective function at earlier period of nerve injury, but the neurotrophic function is uncertain and still need to be studied further.Part two: Experimental Study of the Neuroprotective Effects of FK506 on Spinal Cord Injury in dogsObjective:To explore the neuroprotective effects of FK506 on acute spimal cord injury in dogs and its mechanisms to searching for a new drug in the spinal cord injuty. Methods: Acute spinal cord injury was induced in anesthetized dogs with Allin's technique. Animals were randomly divided into three groups. Group A (n=6)was the control group and received operation but no therapy; group B(n=8), receiving a single dose of FK506(0.18mg/kg)was administered with a arte...
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