PubMed | University of Padua, University of Perugia, University of AucklandAuckland, University of Auckland and 3 more.
Type: | Journal: Frontiers in pharmacology | Year: 2016
Norbormide (NRB) is a unique compound that acts directly on rat vascular myocytes to trigger a contractile process, through an as yet unknown mechanism, which results in the selective contraction of rat peripheral arteries. To gain insight into the mechanisms involved in NRB rat-selective activity, we investigated the subcellular distribution of NRB-AF12, a nitrobenzoxadiazole (NBD)-derivative of NRB, in living NRB-sensitive and NRB-insensitive cells. In both cell types, NRB-AF12 localized to the endoplasmic reticulum (ER), Golgi apparatus, mitochondria, lysosomes, and endosomes; however, in NRB-sensitive cells, the fluorescence also extended to the plasma membrane. NRB-AF12 was rapidly internalized into the cells, could easily be washed out and then reloaded back into the same cells, all with a high degree of reproducibility. Cells exposed for 24 h to NRB-AF12 did not show apparent signs of toxicity, even at concentrations of the dye (10 M) much higher than those required for fluorescence labeling (500 M). The distribution pattern of NRB-AF12 fluorescence was near identical to that of ER-Tracker (Er-Tr), a fluorescent derivative of glibenclamide, a known K