Inhibition of rabbit gastric glucosamine synthetase activity by Cu2+, Zn2+ and Se4+.
The effects of Fe2+, Cu2+, Zn2+ and Se4+ on the activity of glucosamine synthetase, the rate-limiting enzyme of mucus synthesis, in rabbit gastric corporal mucosa were examined. Cu2+, Zn2+ and Se4+ inhibited the glucosamine synthetase activity at concentrations ranging from 1 to 10 microM (Cu2+, 8-98% inhibition; Zn2+, 10-99% inhibition; Se4+, 32-89% inhibition). The inhibitory effects of these three ions were much stronger than that of UDP-N-acetylglúcosamine known as a representative inhibitor of the glucosamine synthetase activity (10 microM, 52% inhibition). Fe2+ had no significant effect on the glucosamine synthetase activity up to 100 microM. These results suggest that Cu2+, Zn2+ and Se4+ can be potent inhibitors of gastric glucosamine synthetase activity.
Fujita
T
T
Department of Hygienic Chemistry, Osaka University of Pharmaceutical Sciences, Japan.
Sakuma
S
S
Takahashi
K
K
Bohtani
Y
Y
Nishida
H
H
Fujimoto
Y
Y
D000818:Animals; D003300:Copper / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005753:Gastric Mucosa / Q000201:enzymology*; D005945:Glutamine-Fructose-6-Phosphate Transaminase (Isomerizing) / Q000187:drug effects* / Q000378:metabolism; D007501:Iron / Q000494:pharmacology*; D008297:Male; D011817:Rabbits; D012643:Selenium / Q000494:pharmacology*; D015032:Zinc / Q000494:pharmacology*
D003300:Copper; D007501:Iron; D005945:Glutamine-Fructose-6-Phosphate Transaminase (Isomerizing); D012643:Selenium; D015032:Zinc