title: Measurement of intracellular pH in isolated bovine articular chondrocytes.
abstract: Cartilage is an avascular tissue, the cells of which are exposed to reduced extracellular pH. The synthesis of cartilage matrix by chondrocytes is pH-sensitive and therefore control of intracellular pH (pHi) is important. We have measured the pHi of chondrocytes in MOPS-buffered saline (pH 7.4) using the fluorescent dye 2',7'-bis-2-(carboxyethyl)-5(6)-carboxyfluorescein. Mean pHi was 7.10 +/- 0.04 (+/- S.E.M., n = 22), and intracellular buffering power was 30 +/- 4 mmol l-1 (pH unit)-1 when pHi was displaced over the range 7.4-7.8 (n = 13). Recovery from acid load was blocked by 100 microM-ethylisopropylamiloride or by removal of extracellular Na+, indicating that these cells possess the Na(+)-H+ antiporter.
authors.affiliation: University Laboratory of Physiology, Oxford.
authors.forename: R J
authors.initials: RJ
authors.lastname: Wilkins
authors.forename: A C
authors.initials: AC
authors.lastname: Hall
mesh_terms: D000818:Animals; D002352:Carrier Proteins / Q000502:physiology; D002358:Cartilage, Articular / Q000166:cytology* / Q000378:metabolism / Q000502:physiology; D002417:Cattle; D005452:Fluoresceins / Q000494:pharmacology; D005453:Fluorescence; D006863:Hydrogen-Ion Concentration; D007596:Joints / Q000166:cytology / Q000378:metabolism / Q000502:physiology; D017923:Sodium-Hydrogen Exchangers
chemical_list: D002352:Carrier Proteins; D005452:Fluoresceins; D017923:Sodium-Hydrogen Exchangers; C043829:2',7'-bis(carboxyethyl)-5(6)-carboxyfluorescein