1999 Fiscal Year Final Research Report Summary
Clarification and control of the mechanism of motor and sensory nerve regeneration after transection
| Project/Area Number |
08407050
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (A)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Orthopaedic surgery
|
|---|
| Research Institution | Shimane Medical University |
|---|
Principal Investigator |
OCHI Mitsuo School of Medicine, Shimane Medical University, Professor, 医学部, 教授 (70177244)
|
|---|
| Project Period (FY) |
1996 – 1999
|
| Keywords | fluoro-Gold / sensory neuron / motoneuron / dorsal root ganglion / spinal anteriorhorn / GAP-43 / sciatic nerve / nerve regeneration |
|---|
| Research Abstract |
1.To determine the effects of the conditioning lesion on the peripheral nerve regeneration, we measured the axonal outgrowths of sensory neurons in response to peripheral nerve injuries using an in vitro tissue culture system of dorsal root ganglia (DRG) with attached nerve stump. It was concluded that the conditioning effect was not merely restricted to the ipsilateral neurons but also affected undamaged sensory neurons of the contralateral DRG. Furthermore we studied if the conditioning effect affected the nerve regeneration in the contralateral nerves in vivo. In results, the initial delay of regeneration was shorter and the expression of IL-1b and TGF-b1 in the contralateral DRG was higher when the contralateral nerves were previously injured.
2.To elucidate the difference in nerve regeneration between sensory neurons and motoneurons, we observed the expression of GAP-43 after transection of the sciatic nerves and confirmed the increased level of GAP-43 in anterior horn (AH) cells f
… More
ollowed that in DRG cells. In addition, we studied the detail of the initial stage of nerve regeneration. After transected and sutured, the sciatic nerves were retransected at the positive pinch site and exposed the proximal stumps to Fluoro-Gold (F-G). The F-G positive labeling was observed more dominantly in DRG cells than the spinal AH cells. These findings suggested that the regeneration of sensory neurons occurred and started earlier than that of motoneurons.
3.The influence of distal nerve segment volume on nerve regeneration in silicon tubes, mass of nerve fragment was examined. The results indicated that the degree of nerve regeneration does not correlate with the volume of distal nerve segment. We also examined whether giving monoclonal antibodies (MoAb) to intercellular adhesion molecule(ICAM-1) and leukocyte function associated antigen (LFA-1) can improve nerve regeneration in allogeneic mice. We conclude that giving MoAb could effectively improve nerve regeneration in grafted allogeneic nerve segments.
4.To date, the expression of cytokines in the neurons in the entrapment neuropathy still remains unclear. We observed the changes of IL-1 and TGF-b1 in the DRG cells during both formation and recovery process, together with electrophysiological changes. After expression of IL-1 reached its peak, expression on TGF-b1 peaked and thereafter changes of motor nerve conduction velocity followed the changes of cytokines in the formation as well as the recovery process. In conclusion, cytokines are deeply involved in the formation as well as the recovery process of entrapment neuropathy. Less
|
