Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)

Editor

Personal info

View

About

Terms

Javascript disabled

Please enable Javascript support in your browser to use this application.

Instructions on how to enable JavaScript on different browsers can be found here: http://www.google.com/support/bin/answer.py?answer=23852.

[edit this page]

Vayuvegula, B. et al.

Correction of altered plasma membrane potentials. A possible mechanism of cyclosporin A and verapamil reversal of pleiotropic drug resistance in neoplasia.

We have recently shown that cyclosporin A (CsA) reverses pleiotropic drug resistance in human acute lymphatic leukemia in vitro and daunorubicin resistance in Ehrlich ascites tumor in vivo. In the present study we examined the mechanisms by which CsA might reverse pleiotropic drug resistance relative to changes in cellular plasma membrane potentials and intracellular calcium ([Ca2+]i). Membrane potentials were measured with DIOC5 dye flow-cytometrically and [Ca2+]i levels with Quin 2 dye spectrofluorimetrically. All pleiotropic ( PDR) drug-resistant tumor sublines had decreased membrane potentials (membrane depolarized) compared with their corresponding drug-sensitive parental tumors. In comparison, the membrane potentials of a control antimetabolite-resistant acute leukemia cell line were unchanged. The basal levels of [Ca2+]i in the PDR sublines were variable compared with those of parental drug-sensitive cell lines. Incubation of all PDR tumor sublines with CsA or verapamil resulted in the restoration of membrane potentials to that characteristic of the corresponding drug-sensitive parental tumor. Cyclosporin A produced variable changes in the levels of [Ca2+]i. These data suggest that alteration of membrane potentials is one of the mechanisms responsible for pleiotropic drug resistance in malignancy and show that this alteration is corrected by CsA and verapamil.[1]

References

Correction of altered plasma membrane potentials. A possible mechanism of cyclosporin A and verapamil reversal of pleiotropic drug resistance in neoplasia. Vayuvegula, B., Slater, L., Meador, J., Gupta, S. Cancer Chemother. Pharmacol. (1988) [Pubmed]

Annotations and hyperlinks in this abstract are from individual authors of WikiGenes or automatically generated by the WikiGenes Data Mining Engine. The abstract is from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.About WikiGenes Open Access Licence Privacy Policy Terms of Use apsburg

The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.