Seventeen commonly used dyes and 16 of their metabolites or derivatives were tested in the Salmonella-mammalian microsome mutagenicity test. Mutagens active with and without added Aroclor-induced rat liver microsome preparations (S9) were 3-aminopyrene, lithol red, methylene blue (USP), methyl yellow, neutral red, and phenol red. Those mutagenic only with S9 activation were 4-aminopyrazolone, 2...

Transient receptor potential vanilloid type 1 (TRPV1) is a nonselective cation channel activated by capsaicin, low pH, and noxious heat and plays a key role in nociception. Understanding mechanisms for functional modulation of TRPV1 has important implications. One characteristic of TRPV1 is that channel activity induced by either capsaicin or other activators can be sensitized or modulated by f...

The properties of several components of outward K(+) currents, including the pharmacological and kinetics profiles as well as the respective molecular correlates, have been identified in mouse cardiac myocytes. Surprisingly little is known with regard to the Ca(2+)-activated ionic currents. We studied the Ca(2+)-activated transient outward currents in mouse ventricular myocytes. We have identif...

An inwardly rectifying swelling- and meiotic cell cycle-regulated anion current carried by the ClC channel splice variant CLH-3b dominates the whole cell conductance of the Caenorhabditis elegans oocyte. Oocytes also express a novel outwardly rectifying anion current termed I(Cl,OR). We recently identified a worm strain carrying a null allele of the clh-3 gene and utilized oocytes from these an...

The intraerythrocytic malaria parasite exerts tight control over its ionic composition. In this study, a combination of fluorescent ion indicators and (36)Cl(-) flux measurements was used to investigate the transport of Cl(-) and the Cl(-)-dependent transport of "H(+)-equivalents" in mature (trophozoite stage) parasites, isolated from their host erythrocytes. Removal of extracellular Cl(-), res...

We have used the whole-cell patch-clamp technique to examine the ionic basis for a transient outward current in rabbit ventricular myocytes. High concentrations of intracellular calcium buffer prevented the current, isoproterenol increased it, and cadmium, nisoldipine, ryanodine, or caffeine blocked it. These data are consistent with a current that is calcium activated, by the calcium transient...

Human airway serous cells secrete antibiotic-rich fluid, but, in cystic fibrosis (CF), Cl--dependent fluid secretion is impaired by defects in CF transmembrane conductance regulator (CFTR) Cl-channels. Typically, CF disrupts adenosine 3',5'-cyclic monophosphate (cAMP)-mediated Cl- secretion but spares Ca2+-mediated secretion. However, in CF airway glands, Ca2+-mediated secretion is also greatly...