Multiphoton spectral analysis of benzo[a]pyrene uptake and metabolism in breast epithelial cell lines.

Quantification of polycyclic aromatic hydrocarbons (PAH) and their metabolites within living cells and tissues in real time using fluorescence methods is complicated due to overlaping excitation and/or emission spectra of metabolites. In this study, simultaneous analysis of several metabolites of a prototype carcinogenic PAH, benzo[a]pyrene (BaP) in undifferentiated (MCF10A) and differentiated (MCF10CA1h) breast cancer cells was performed using single-cell multiphoton spectral analysis. The two cell types were selected for this study because they are known to have differences in BaP uptake and metabolism and induction of aryl hydrocarbon receptor-dependent ethoxyresorufin-O-deethylase (EROD) activity.

Effects of benzo-a-pyrene on oxytocin-induced Ca2+ oscillations in myometrial cells.

Benzo-a-pyrene (BaP) is a polycyclic aromatic hydrocarbon that exists as a major environmental pollutant. The effect of this carcinogen/mutagen upon myometrial Ca(2+) signaling in a human myometrial cell line (PHM1) was examined. Exposure of cells to BaP did not alter basal Ca(2+) levels or the inositol(1,4,5) trisphosphate-releasable Ca(2+) pool.

Characterization of calcium oscillations in normal and benzo[a]pyrene-treated clone 9 cells.

Intracellular Ca2+ oscillations induced by oxytocin and vasopressin were analyzed in a rat liver cell line (Clone 9) in order to identify mechanisms by which benzo[a]pyrene (BaP) alters Ca2+ signaling patterns in these cells. Clone 9 cells exhibit an initial Ca2+ spike, followed by Ca2+ oscillations upon oxytocin or vasopressin treatment. The range of frequencies (maximum 110 mHz) was dependent on agonist concentration with a constant amplitude less than or equal to the amount of Ca2+ generated from the inositol trisphosphate (InsP(3))-sensitive pool.