INCREASED LEVELS OF MITOGEN-ACTIVATED PROTEIN-KINASE (MAP-K) DETECTEDIN THE INJURED ADULT-MOUSE SCIATIC-NERVE

Adult mouse sciatic nerves (SNs) with attached dorsal root ganglia (DR G) were analysed for the presence of mitogen activated protein kinase (MAP-K) during normal and regenerative conditions. By immunohistochemi stry, MAP-K was found to be present in the normal nerve at low levels in both Schwann cells and DRG nerve cell bodies, with a profoundly inc reased expression during regeneration. In axonal outgrowth assays, tre atment with 2 mM 2-aminopurine (2-AP), a MAP-K antagonist, inhibited t he regeneration of axons from the SN as well as from the cultured supe rior cervical ganglia. The reduced outgrowth was probably not due to t oxic effects of the drug since the ganglionic protein synthesis was no t inhibited. It is possible that 2-AP interferes with regeneration-rel ated events by inhibition of MAP-K.