title: Ferrous [Fe++] but not ferric [Fe] ions inhibit de novo formation of calcium pyrophosphate dihydrate crystals: possible relationships to chondrocalcinosis and hemochromatosis.
abstract: To determine the physical-chemical effects of [Fe++] and [Fe ] on calcium pyrophosphate dihydrate (CPPD) crystal formation de novo, we studied CPPD crystal formation in an established model aqueous solution mixture system using physiological concentrations of Na+, Mg++, Ca++, C1-. We found that [Fe++] greater than 1 microM or [Fe ] greater than or equal to 100 microM inhibits CPPD crystal formation under conditions of [Ca++] = 1.5 mM, [Pi] = 0.1 mM, and [PPi] = 0.1 mM that simulate CPPD formation in vivo. These experiments suggest that at biological concentrations, Fe++ acts to inhibit CPPD formation but that [Fe++] depletion therapy by removal of inhibition effects may facilitate CPPD crystal formation in articular tissues.
authors.affiliation: Department of Pathology, Mount Sinai Hospital, Toronto, Canada.
authors.forename: P T
authors.initials: PT
authors.lastname: Cheng
authors.forename: K P
authors.initials: KP
authors.lastname: Pritzker
mesh_terms: D002131:Calcium Pyrophosphate / Q000037:antagonists & inhibitors* / Q000096:biosynthesis; D002805:Chondrocalcinosis / Q000378:metabolism*; D003460:Crystallization; D011756:Diphosphates / Q000037:antagonists & inhibitors*; D005290:Ferric Compounds / Q000494:pharmacology; D005296:Ferrous Compounds / Q000494:pharmacology*; D006432:Hemochromatosis / Q000378:metabolism*; D006801:Humans
chemical_list: D011756:Diphosphates; D005290:Ferric Compounds; D005296:Ferrous Compounds; D002131:Calcium Pyrophosphate