Biomaterial Database

A specific enzyme assay for aminopeptidase M in rat brain. 1992

T J Gillespie, and P N Konings, and B J Merrill, and T P Davis

Department of Pharmacology, College of Medicine, University of Arizona, Tucson 85724.

A specific enzyme assay for aminopeptidase M (APM) activity on rat brain membranes has been developed through selective use of enzyme inhibitors. Amastatin was the most potent inhibitor (amastatin > actinonin > MDL73347 > bestatin) for purified porcine kidney APM, giving 98% inhibition at a 6 microM concentration, while actinonin, yielded only 57% inhibition at this concentration. Puromycin (10 microM) was used to inhibit puromycin-sensitive aminopeptidase activity in the rat brain membrane preparation. Puromycin (10 microM) had only a slight effect on the Km of porcine kidney APM, and had negligible effect on APM velocity at the high substrate concentration (2 mM) used in the APM assay. The assay produced a linear accumulation of product for increasing amount of rat brain membranes used, and for increasing incubation time. The Km of APM on rat brain membranes for L-Leucine-p-nitroanilide (0.383 mM) was similar to the Km of purified porcine kidney APM (0.558 mM). APM-activity, involved in the metabolism of several biologically important neuropeptides in different brain regions, can be specifically measured with this enzyme assay.

UI	MeSH Term	Description	Entries
D007668	Kidney	Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.	Kidneys
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008297	Male		Males
D002540	Cerebral Cortex	The thin layer of GRAY MATTER on the surface of the CEREBRAL HEMISPHERES that develops from the TELENCEPHALON and folds into gyri and sulci. It reaches its highest development in humans and is responsible for intellectual faculties and higher mental functions.	Allocortex,Archipallium,Cortex Cerebri,Cortical Plate,Paleocortex,Periallocortex,Allocortices,Archipalliums,Cerebral Cortices,Cortex Cerebrus,Cortex, Cerebral,Cortical Plates,Paleocortices,Periallocortices,Plate, Cortical
D004791	Enzyme Inhibitors	Compounds or agents that combine with an enzyme in such a manner as to prevent the normal substrate-enzyme combination and the catalytic reaction.	Enzyme Inhibitor,Inhibitor, Enzyme,Inhibitors, Enzyme
D000626	Aminopeptidases	A subclass of EXOPEPTIDASES that act on the free N terminus end of a polypeptide liberating a single amino acid residue. EC 3.4.11.	Aminopeptidase
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D017207	Rats, Sprague-Dawley	A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.	Holtzman Rat,Rats, Holtzman,Sprague-Dawley Rat,Rats, Sprague Dawley,Holtzman Rats,Rat, Holtzman,Rat, Sprague-Dawley,Sprague Dawley Rat,Sprague Dawley Rats,Sprague-Dawley Rats
D051381	Rats	The common name for the genus Rattus.	Rattus,Rats, Laboratory,Rats, Norway,Rattus norvegicus,Laboratory Rat,Laboratory Rats,Norway Rat,Norway Rats,Rat,Rat, Laboratory,Rat, Norway,norvegicus, Rattus
D018826	CD13 Antigens	Zinc-binding metalloproteases that are members of the type II integral membrane metalloproteases. They are expressed by GRANULOCYTES; MONOCYTES; and their precursors as well as by various non-hematopoietic cells. They release an N-terminal amino acid from a peptide, amide or arylamide.	ANPEP Protein,Aminopeptidase M,Aminopeptidase N,Antigens, CD13,Membrane Alanyl Aminopeptidase,Alanine Aminopeptidase,Alanyl Aminopeptidase,Amino-oligopeptidase,Aminooligopeptidase,CD13 Antigen,Antigen, CD13,Protein, ANPEP