[Study on substance P immunoreactivity after acute crush injury to facial nerve]

This paper presents the change in substance P immunoreactivity (SP-IR) after acute crush injury to the vertical part of facial nerve of normal cats by using immunohistochemical and immunocytochemical techniques combined with immunoelectronic microscopy. The electroneuromyogram (ENOG) shows that the cats have suffered from fully peripheral facial paralysis. It is found that the SP-IR positive products and fibers increase in the other part of facial nerve (including the non-injured part of vertical segment and level segment) after injury, especially six days later. As a result, it is suggested that the regeneration and repair of facial nerve might be in close relationship with substance P after acute crush injury to it.