Subcellular distribution of soluble and membrane-bound Leu-, Arg- and Asp-beta-naphthylamide-hydrolysing activities in rat brain.
Subcellular distribution of soluble and membrane-bound Leu-, Arg- and Asp-beta-naphthylamide hydrolysing activities (arylamidase activity) was studied from left and right rat brains, each including hemisphere, cerebellum and brain stem. Both soluble Leu- and Arg-beta-naphthylamide hydrolysing activities showed the highest levels in the synaptosomal fraction. However, the microsomal fraction presented the highest levels when membrane-bound activity was assayed. When we used Asp-beta-naphthylamide as substrate, there were no differences among fractions in the membrane-bound activity, and the highest soluble activity was present at the mitochondrial level. Two different patterns in the subcellular distribution of enzymatic activity were observed: One of them was the result of the use of Leu- or Arg-beta-naphthylamide as substrate and the other when Asp-beta-naphthylamide was employed. No differences between left and right brains in soluble or membrane-bound activities were found.
Ramirez
M
M
Department of Physiology, Medical School, University of the Basque Country, Bilbao, Spain.
Arechaga
G
G
Lardelli
P
P
Venzon
D
D
de Gandarias
J M
JM
D000626:Aminopeptidases / Q000378:metabolism*; D000818:Animals; D001120:Arginine / Q000031:analogs & derivatives* / Q000378:metabolism; D001224:Aspartic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D001921:Brain / Q000201:enzymology*; D002462:Cell Membrane / Q000378:metabolism; D007930:Leucine / Q000031:analogs & derivatives* / Q000378:metabolism; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012995:Solubility
D001224:Aspartic Acid; C044335:aspartic acid beta-naphthylamide; C029772:arginine beta-naphthylamide; C040135:leucine-beta-naphthylamide; D001120:Arginine; D000626:Aminopeptidases; D007930:Leucine