2002 Fiscal Year Final Research Report Summary
Glial introduction of resenerating axons
Project/Area Number |
13680818
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Nerve anatomy/Neuropathology
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Research Institution | Tokai University (2002) 福井医科大学 (2001) |
Principal Investigator |
TORIGOE Kojun Tokai University, School of Medicine, Professor, 医学部, 教授 (50126603)
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Project Period (FY) |
2001 – 2002
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Keywords | neural regeneration / glia / Schwann cell / myelin inhibitor / myelin-associated glycoprotein / demyelination / film model / glial introduction |
Research Abstract |
In axonal regeneration after a peripheral nerve injury, firstly, we studied the effect of distal nerve segments on the regeneration of axons from the proximal stump of a transected common peroneal nerve in mice. The elongation of regenerating axons was promoted by placing nerve segments that had been isolated by transection 5 to 6 days earlier (5-day to 6-day nerve segments) within 1.5 mm of the proximal stump. In contrast, axons were inhibited from sprouting and elongating when 7-day to 14-day nerve segments were used. Western blotting revealed the spread of myelin-associated glycoprotein (JMAG) from 7-day nerve segments, and electrophoresis of substances released by 7-ll-day nerve segments detected an approximately 56 KD polypeptide that corresponds to an extracellular domain of MAG Local application of a solution containing antibodies to MAG completely 'blocked the inhibition of axonal outgrowth exerted by 7-day nerve segments. In some experiments applied to an effect of a conditioning lesion under a suppression of MAG, we suggest that axonal inhibition by MAG is mediated by a local response near the MAG receptor rather than by an effect on metabolism in neural somata. Secondarily, after local application of a solution of anti-MAG antibodies, we showed that regenerating axons sprouted and elongated accompanying with Schwann cells migrating from a parent nerve (proximal type of migratory Schwann cells). Schwann cells migrated from a distal nerve segmentas well and took a line, forming a bridge with proximal type of migratory Schwann cells. As soon as contacting witproximal type of migratory Schwanncells, distal type of Schwann cells took a line, indicating that 7-14-day distal nervesegments hava a role of inducing axons towards a bund of Bungner by a bridge of two types of migratory Schwann cells.
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Research Products
(8 results)