Biomaterial Database

Control of intracellular pH in rat calvarial osteoblasts: coexistence of both chloride-bicarbonate and sodium-hydrogen exchange. 1988

C R Redhead, and P F Baker

Physiology Department, Kings College London, Great Britain.

Intracellular pH was monitored continuously in cultured rat calvarial osteoblasts using the pH-sensitive fluorescent dye bis carboxyethyl carboxyfluorescein (BCECF), loaded into the cells as its membrane permeant ester. Recovery from an intracellular acid load generated by exposure to NH4Cl was unaffected by the anion exchange inhibitors 4-acetamido-4'-isothiocyanato-stilbene-2,2'-disuphonic acid (SITS) and 4,4'-diisothiocyanato-stilbene 2,2'-disuphonic acid (DIDS) (100 microM), but blocked by the sodium-hydrogen exchange inhibitor amiloride (1 mM) and dependent on external sodium, suggesting that recovery is brought about by a sodium-hydrogen exchanger in the plasma membrane. The cells do, however, possess a SITS-sensitive chloride-bicarbonate exchanger, because iso-osmotic replacement of chloride by gluconate leads to intracellular alkalinization, that is inhibited by SITS, but independent of external sodium. Parathyroid hormone brings about an intracellular acidification, which may be due to an inhibiton of sodium-hydrogen exchange.

UI	MeSH Term	Description	Entries
D010006	Osteoblasts	Bone-forming cells which secrete an EXTRACELLULAR MATRIX. HYDROXYAPATITE crystals are then deposited into the matrix to form bone.	Osteoblast
D010281	Parathyroid Hormone	A polypeptide hormone (84 amino acid residues) secreted by the PARATHYROID GLANDS which performs the essential role of maintaining intracellular CALCIUM levels in the body. Parathyroid hormone increases intracellular calcium by promoting the release of CALCIUM from BONE, increases the intestinal absorption of calcium, increases the renal tubular reabsorption of calcium, and increases the renal excretion of phosphates.	Natpara,PTH (1-84),PTH(1-34),Parathormone,Parathyrin,Parathyroid Hormone (1-34),Parathyroid Hormone (1-84),Parathyroid Hormone Peptide (1-34),Hormone, Parathyroid
D010446	Peptide Fragments	Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.	Peptide Fragment,Fragment, Peptide,Fragments, Peptide
D002352	Carrier Proteins	Proteins that bind or transport specific substances in the blood, within the cell, or across cell membranes.	Binding Proteins,Carrier Protein,Transport Protein,Transport Proteins,Binding Protein,Protein, Carrier,Proteins, Carrier
D006859	Hydrogen	The first chemical element in the periodic table with atomic symbol H, and atomic number 1. Protium (atomic weight 1) is by far the most common hydrogen isotope. Hydrogen also exists as the stable isotope DEUTERIUM (atomic weight 2) and the radioactive isotope TRITIUM (atomic weight 3). Hydrogen forms into a diatomic molecule at room temperature and appears as a highly flammable colorless and odorless gas.	Protium,Hydrogen-1
D006863	Hydrogen-Ion Concentration	The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH	pH,Concentration, Hydrogen-Ion,Concentrations, Hydrogen-Ion,Hydrogen Ion Concentration,Hydrogen-Ion Concentrations
D000136	Acid-Base Equilibrium	The balance between acids and bases in the BODY FLUIDS. The pH (HYDROGEN-ION CONCENTRATION) of the arterial BLOOD provides an index for the total body acid-base balance.	Anion Gap,Acid-Base Balance,Acid Base Balance,Acid Base Equilibrium,Anion Gaps,Balance, Acid-Base,Equilibrium, Acid-Base,Gap, Anion,Gaps, Anion
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
D012886	Skull	The SKELETON of the HEAD including the FACIAL BONES and the bones enclosing the BRAIN.	Calvaria,Cranium,Calvarium,Skulls
D012964	Sodium	A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.	Sodium Ion Level,Sodium-23,Ion Level, Sodium,Level, Sodium Ion,Sodium 23