T. Kato et al., AXONAL TRANSPORTS OF BOC-GLY-ARG-ARG-MCA HYDROLYZING ENZYME IN RAT SCIATIC-NERVES, Neurochemistry international, 32(2), 1998, pp. 163-170
Study on neural axon transport is a very useful method to find a neuro
n-specific protease. In the present study, the enzyme activity (releas
e of 7-amino-4-methyl-coumarin from cyl-L-arginyl-L-arginine-4-methylc
oumaryl-7-amide) was measured in the proximal, middle, and distal segm
ents between 12 and 120 h after double ligations of rat sciatic nerves
to find precursor processing enzyme specific for pair of basic amino
acid residue. The enzyme activity was significantly increased not only
in the proximal but also in the distal segments 12-120 h after the li
gation, and the maximal enzyme activity was found in both segments at
72 h. The enzyme activity eluted by anion exchange chromatography of t
he proximal segment showed at least three peaks, and was slightly high
er than the activity of the distal one. The activity in the middle seg
ment was very low in comparison with the activity in the proximal and
distal segments. These data indicate that some of the enzymes specific
for pair of basic amino acid residue are transported by both anterogr
ade and retrograde axonal flow, and may undergo a neuron-specific proc
essing. (C) 1998 Elsevier Science Ltd. All rights reserved.