Isolation and identification of an endogenous inhibitor of enkephalin-degrading enzymes from bovine spinal cord.
We isolated a potent inhibitor of enkephalin-degrading enzymes from bovine spinal cord and determined its amino-acid sequence and inhibitory activity toward enkephalin-degrading enzymes. This new substance, designated spinorphin, is composed of a heptapeptide (Leu-Val-Val-Tyr-Pro-Trp-Thr). The inhibitory activity (IC50) of this new substance toward enkephalin-degrading enzymes, purified from monkey brain, was found to be 3.3 micrograms/ml against aminopeptidase, 1.4 micrograms/ml against dipeptidyl aminopeptidase, 2.4 micrograms/ml against angiotensin-converting enzyme, and 10 micrograms/ml against enkephalinase. This new substance did not show inhibitory activity toward enkephalin degrading enzymes purified from kidney and blood. Above results suggest that this substance is a new neuromodulator in the spinal cord.
Nishimura
K
K
Department of Anesthesiology, Juntendo University, School of Medicine, Tokyo, Japan.
Hazato
T
T
D000595:Amino Acid Sequence; D000626:Aminopeptidases / Q000037:antagonists & inhibitors; D000818:Animals; D001921:Brain / Q000201:enzymology; D002417:Cattle; D002462:Cell Membrane / Q000201:enzymology; D002852:Chromatography, Ion Exchange; D006801:Humans; D007668:Kidney / Q000201:enzymology; D008969:Molecular Sequence Data; D015260:Neprilysin / Q000037:antagonists & inhibitors* / Q000302:isolation & purification; D009842:Oligopeptides / Q000302:isolation & purification* / Q000494:pharmacology; D016339:Spectrometry, Mass, Fast Atom Bombardment; D013116:Spinal Cord / Q000201:enzymology / Q000378:metabolism*; D013552:Swine
D009842:Oligopeptides; C082392:spinorphin; D000626:Aminopeptidases; D015260:Neprilysin