ADAMTS-4 expression and activity in the injured spinal cord of rats. ADAMTS-4 in the spinal cord tissue lysates was slightly increased after spinal cord injury compared with the sham-operated rats (Western blot analysis) (A). The proteolytic activity of ADAMTS-4 was significantly increased by about 1.4-fold in the rat spinal cord after injury (B). Enzymatic activities of tissue extracts of the spinal cord (1 cm around the lesion) were measured. *, P < 0.01. ADAMTS-4 mRNA was mainly expressed by astrocytes and microglia, but not neurons (C).