Distribution of prolyl endopeptidase activities in rat and human brain.
Prolyl endopeptidase is a proteolytic enzyme which could have a neuropeptide catabolising role in the central nervous system. Although prolyl endopeptidase has been described as a cytosolic enzyme, it has become clear that it can also be found in particulate form. The regional and subcellular distribution of this enzyme was evaluated in rat and human brain. The activity of the enzyme was higher in the human than in the rat brain. In the human brain, the activity levels of both soluble and particulate prolyl endopeptidase were the highest in frontal, parietal and occipital cortices and the lowest in the cerebellum. In the rat brain, the regional distribution of the enzyme was more homogeneous. The activity in all the areas of the central nervous system is higher than in peripheral tissues. Subcellular distribution of the enzyme in the brain indicates that prolyl endopeptidase was higher in the cytosolic fraction than in the particulate fractions. The particulate form was enriched in the synaptosomal and the myelinic membranes. The high activity of prolyl endopeptidase in the human cortex suggests that prolyl endopeptidase could play a role in the functions of this brain area.
Irazusta
Jon
J
Department of Physiology, Medical School, University of the Basque Country, Leioa, P.O. Box 699, 48,080 Bilbao, Spain. ofpirasj@lg.ehu.es
Larrinaga
Gorka
G
González-Maeso
Javier
J
Gil
Javier
J
Meana
J Javier
JJ
Casis
Luis
L
D015087:2',3'-Cyclic-Nucleotide Phosphodiesterases / Q000032:analysis; D000293:Adolescent; D000328:Adult; D000818:Animals; D001921:Brain / Q000201:enzymology*; D002531:Cerebellum / Q000201:enzymology; D005625:Frontal Lobe / Q000201:enzymology; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000032:analysis; D008861:Microsomes / Q000201:enzymology; D008875:Middle Aged; D009245:NADH Dehydrogenase / Q000032:analysis; D009419:Nerve Tissue Proteins / Q000032:analysis*; D009778:Occipital Lobe / Q000201:enzymology; D009928:Organ Specificity; D010296:Parietal Lobe / Q000201:enzymology; D011180:Postmortem Changes; D000085822:Prolyl Oligopeptidases; D051381:Rats; D017207:Rats, Sprague-Dawley; D012697:Serine Endopeptidases / Q000032:analysis*; D013347:Subcellular Fractions / Q000201:enzymology; D013385:Succinate Dehydrogenase / Q000032:analysis; D013574:Synaptosomes / Q000201:enzymology; D014781:Viscera / Q000201:enzymology
D009419:Nerve Tissue Proteins; D007770:L-Lactate Dehydrogenase; D013385:Succinate Dehydrogenase; D009245:NADH Dehydrogenase; D015087:2',3'-Cyclic-Nucleotide Phosphodiesterases; D012697:Serine Endopeptidases; C000705287:PREPL protein, human; D000085822:Prolyl Oligopeptidases