Many teleostean fish, including rainbow trout, regulate red blood cell (RBC) pH (pH(i)) in the presence of a stress-induced acidosis such as hypoxia, hypercapnia, or exhaustive exercise. This is accomplished through activation of RBC Na+/H+ exchange (beta-NHE), ultimately minimizing impairment to oxygen transport. Presence and characterization of the RBC beta-NHE in fish is best tested in blood...

The overexpression of BI-1 induces an acidic extracellular pH due to alterations of mitochondrial function, leading to cancer metastasis through anaerobic glucose metabolism. In this study, ion transporters such as sodium hydrogen exchangers (NHE) and monoamine carboxylate transporters (MCTs) were studied in BI-1-overexpressing HT1080 cells (BI-1 cells). The extracellular pH became acidic as cu...

Oligodendrocytes (OLs) are cells that produce myelin in the central nervous system. Here we use ratiometric pH indicator dye to analyze intracellular pH in OLs in culture. The results reveal alkaline microdomains, which predominate in the perikaryon and proximal dendrites, and acidic microdomains, which predominate in distal dendrites. Spatial nonuniformity of pH is generated by differential su...

Avian intrapulmonary chemoreceptors (IPC) are vagal respiratory afferents that are inhibited by high lung Pco(2) and excited by low lung Pco(2). Previous work suggests that increased CO(2) inhibits IPC by acidifying intracellular pH (pH(i)) and that pH(i) is determined by a kinetic balance between the rate of intracellular carbonic anhydrase-catalyzed CO(2) hydration/dehydration and transmembra...

Inhibition of the renal brush border membrane (BBM) Na/H exchanger by cAMP-dependent protein kinase, PKA, requires participation of a recently cloned regulatory cofactor, Na/H exchanger-regulatory factor (NHE-RF). As deduced from the cDNA of this 358-amino acid protein, amino acids 11-101 and amino acids 150-241 of the NHE-RF protein share 74% overall homology suggesting duplication of these PD...

Background and Objective: Bacillus cereus is responsible for several outbreaks of foodborne diseases. Therefore, the purpose of the study was to replace routine culture testing, by employing PCR directly from food to detect the bacteria and its enterotoxins. Methods: In the present study, a total of 75 Kibda sandwiches, Sausage sandwiches, Luncheon chicken, Luncheon meat and shawarma sandwiche...

Na+/H+ exchange in vertebrates is thought to be electroneutral and insensitive to the membrane voltage. This basic concept has been challenged by recent reports of antiport-associated currents in the turtle colon epithelium (Post and Dawson, 1992, 1994). To determine the electrogenicity of mammalian antiporters, we used the whole-cell patch clamp technique combined with microfluorimetric measur...

The avascular nature of articular cartilage means that chondrocytes are dependent on the diffusion of O2 from the synovial fluid and subchondral bone. As a result, cartilage has a relatively low ambient O2 tension, estimated at between 5% and 7% O2. In addition, synovial, and cartilage, O2 tensions can fall to very low levels in inflammatory conditions. Low O2 tensions can affect ion homeostasi...

Excessive production of endothelin-1 (ET-1), a potent vasoconstrictor, occurs with several forms of pulmonary hypertension. In addition to modulating vasomotor tone, ET-1 can potentiate pulmonary arterial smooth muscle cell (PASMC) growth and migration, both of which contribute to the vascular remodeling that occurs during the development of pulmonary hypertension. It is well established that c...