NADPH-dependent generation of H2O2 in a thyroid particulate fraction requires Ca2+.
The action of Ca2+ on H2O2 formation catalyzed by an NADPH-dependent H2O2-generating system was studied in a thyroid particulate fraction. It was shown that H2O2 formation was inhibited by EGTA and restored in the presence of micromolar concentrations of free Ca2+, and that Mg2+ was unable to restore the activity of the EGTA-inhibited particulate fraction. Consequently, NADPH-dependent H2O2 formation requires Ca2+, and the Ca2+ stimulation of this process is specific and reversible.
D000818:Animals; D002118:Calcium / Q000494:pharmacology*; D004533:Egtazic Acid / Q000494:pharmacology; D006861:Hydrogen Peroxide / Q000378:metabolism*; D008274:Magnesium / Q000494:pharmacology; D009249:NADP / Q000494:pharmacology*; D013552:Swine; D013696:Temperature; D013961:Thyroid Gland / Q000187:drug effects / Q000378:metabolism*; D013972:Thyrotropin / Q000494:pharmacology
D004533:Egtazic Acid; D009249:NADP; D013972:Thyrotropin; D006861:Hydrogen Peroxide; D008274:Magnesium; D002118:Calcium