A MORPHOLOGICAL-STUDY OF EXPERIMENTAL MONONEUROPATHY IN THE RAT - EARLY ISCHEMIC CHANGES

This paper describes early morphological changes following the placeme nt of four loose ligatures round the rat sciatic nerve, a method used to produce altered pain-related behaviour. The ligatures were tied so as not to constrict the nerve, but there was compression of some epine urial blood vessels. This mild lesion caused behavioural changes and n erve fiber abnormalities within 8.5 h. The distribution of nerve fiber changes was patchy, and initially due to stagnant ischemia, with necr osis of Schwann cells and evidence of axonal stasis. By 48 h, endoneur ial oedema increased leading to a compressive lesion and eventually to severe nerve fiber degeneration.