Membrane transport pathways for transplacental transfer of CO2/HCO3 were investigated by assessing the possible presence of a Cl/HCO3 exchange mechanism in the maternal-facing membrane of human placental epithelial cells. Cl/HCO3 exchange was tested for in preparations of purified brush border membrane vesicles by 36Cl tracer flux measurements and determinations of acridine orange fluorescence ...

Pharmacology of CFTR Chloride Channel Activity. Physiol. Rev. 79, Suppl.: S109-S144, 1999. - The pharmacology of cystic fibrosis transmembrane conductance regulator (CFTR) is at an early stage of development. Here we attempt to review the status of those compounds that modulate the Cl- channel activity of CFTR. Three classes of compounds, the sulfonylureas, the disulfonic stilbenes, and the ary...

The synthesis and characterization of a novel fluorophore(1), with potential application as an optical brightener are reported. This compound was prepared by reacting 4,4-diaminostilbene-2,2-disulfonic acid with cyanuric chloride in the presence of Na2CO3 followed by the addition of trityl aniline. Solution and solid state fluorescence demonstrated a strong blue/purple emission centered at 450 ...

We characterized a voltage-dependent ionic current in dental pulp cells on dental pulp slices using a nystatin perforated-patch recording configuration. The outward currents in dental pulp cells were inhibited by the following channel blockers: 1) Ca(2+)-free extracellular solution containing 10 mM Ba2+, 2) extracellular 400 nM apamin and 3) extracellular 300 nM 4,4'-diisothiocyanatostilbene-2,...

We investigated the membrane properties and dominant ionic conductances in the plasma membrane of the calcifying marine phytoplankton Coccolithus pelagicus using the patch-clamp technique. Whole-cell recordings obtained from decalcified cells revealed a dominant anion conductance in response to membrane hyperpolarization. Ion substitution showed that the anion channels were selective for Cl(-) ...

The modulation of intracellular pH by activation of metabotropic glutamate receptors was investigated in cultured and acutely dissociated rat astrocytes. One minute superfusion of 100 microM (1S,3R)-1-aminocyclopentane-1, 3-dicarboxcylic acid (ACPD) evoked an alkaline shift of 0.13 +/- 0. 013 (mean +/- SE) and 0.16 +/- 0.03 pH units in cultured (cortical or cerebellar) and acutely dissociated c...

Nicotinic acid adenine dinucleotide phosphate (NAADP) has been shown to release intracellular Ca(2+) in several types of cells. We have used Ca(2+)-sensitive fluorescent dyes (Fura-2, Fluo-4) to measure intracellular Ca(2+) in astrocytes in culture and in situ. Bath-applied NAADP elicited a reversible and concentration-dependent Ca(2+) rise in up to 90% of astrocytes in culture (EC(50)=7 microM...

We found the colorimetric reaction of Tiron (1,2-dihydroxybenzene-3,5-disulfonic acid) and molybdate suitable for optical quantification of chemical reaction during fluid–fluid mixing in laboratory chambers. This reaction consists of two colorless reagents that mix to rapidly form colored, stable, soluble products. These products can be digitally imaged and quantified using light absorbance to ...

Photo-aligned VAN-LCD was developed using the photosensitive polyimide (PI) JALC 2021-R2, illuminated by obliquely incident non-polarized light. It has been shown that the combination of these aligning materials with newly developed derivative of sodium salt of benzidine –3,3’-disulfonic acid (SD-1) gives a reliable and a good electro-optical performance. The response time, contrast ratio and V...