Biomaterial Database

Inhibitory effect of zinc and copper on phosphatase activity in the brain cytosol of rats: involvement of SH groups. 1998

Y Hanahisa, and M Yamaguchi

Laboratory of Endocrinology and Molecular Metabolism, Graduate School of Nutritional Sciences, University of Shizuoka, Japan.

The effect of various metal ions on neutral phosphatase activity in the brain cytosol of rats was investigated. p-Nitrophenylphosphate was used as the substrate for the enzyme assay. Brain cytosolic phosphatase activity was significantly decreased by the presence of zinc or copper in the range of 10(-5) to 10(-3) M in the enzyme reaction mixture, while it was significantly increased by manganese, nickel or cobalt (10(-5) to 10(-3) M). Calcium (10(-5) to 10(-3) M) did not have an appreciable effect on brain cytosolic phosphatase activity. The inhibitory effect of zinc (10(-5) M) or copper (10(-5) M) on phosphatase activity was seen in the presence of manganese, nickel or cobalt with 10(-4) M concentration, indicating a potent inhibitory effect of these metals. Zinc or copper-decreased phosphatase activity was clearly prevented by dithiothreitol (5 mM), although the effect of each metal was further enhanced by N-ethylmaleimide (5 mM), suggesting that the metals act on the SH-groups of enzyme. Moreover, the inhibitory effect of zinc (10(-5) M) was significantly enhanced by S-100A (10(-6) M) or calbindin (10(-7) M), although neither protein had any effect in the presence of calcium (10(-5) M) or copper (10(-5) M). These results suggests that zinc has an unique role in the regulation of neutral phosphatase activity in rat brain cytosol.

UI	MeSH Term	Description	Entries
D010744	Phosphoric Monoester Hydrolases	A group of hydrolases which catalyze the hydrolysis of monophosphoric esters with the production of one mole of orthophosphate.	Phosphatase,Phosphatases,Phosphohydrolase,Phosphohydrolases,Phosphomonoesterase,Phosphomonoesterases,Phosphoric Monoester Hydrolase,Hydrolase, Phosphoric Monoester,Hydrolases, Phosphoric Monoester,Monoester Hydrolase, Phosphoric
D001921	Brain	The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.	Encephalon
D003300	Copper	A heavy metal trace element with the atomic symbol Cu, atomic number 29, and atomic weight 63.55.	Copper-63,Copper 63
D003600	Cytosol	Intracellular fluid from the cytoplasm after removal of ORGANELLES and other insoluble cytoplasmic components.	Cytosols
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
D005260	Female		Females
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
D013438	Sulfhydryl Compounds	Compounds containing the -SH radical.	Mercaptan,Mercapto Compounds,Sulfhydryl Compound,Thiol,Thiols,Mercaptans,Compound, Sulfhydryl,Compounds, Mercapto,Compounds, Sulfhydryl
D015032	Zinc	A metallic element of atomic number 30 and atomic weight 65.38. It is a necessary trace element in the diet, forming an essential part of many enzymes, and playing an important role in protein synthesis and in cell division. Zinc deficiency is associated with ANEMIA, short stature, HYPOGONADISM, impaired WOUND HEALING, and geophagia. It is known by the symbol Zn.
D017208	Rats, Wistar	A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.	Wistar Rat,Rat, Wistar,Wistar Rats