Cardiovascular Diseases Poster Session

Re: poster 138

Adel Elmoselhi
elmosel@fhs.csu.mcmaster.ca

On Fri Dec 4, grover wrote
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>Dr. Elmoselhi: Great presentation. Hope you have fun at the meeting.You have used fresh arteries for the contractility experiments and cultured cells for Cai measurements. Is it possible that this difference in the peroxide sensitivity siply represents a change in cells upon culturing? Do you have some evidence that it does not? If this simply a change on culturing the cells, how do you explain your results?
>

Thank very much Dr. Grover. Even though its not as much fun as travelling to attend a conference, I am enjoying surfing through these very interesting works and ideas. Regarding your question, The culture smooth muscles cells (passage four), that we used in this study, were confirmed to retain their phenotypes according to the following criteria: a) the cells protein reacted with -actin smooth muscle antibodies in Western blots provide an -actin band (45kDa), and with SERCA2b selective antibodies give 115kDa bands, b) the cells retained the typical spindle shape of the smooth muscle cells, and c) all the cells reacted with -actin antibodies using immunohistochemical staining (A.B. Elmoselhi et al, 1995, Mol. Cell. Biochem., 151: 149-155)
Moreover, the possible alteration of the Ca2+ sensitive dye used (fluo-3) by peroxide was also eliminated, since peroxide concentration below 10 mM did not affect the fluorescence or binding characteristics of fluo-3 ( Sandhu V. el al, 1998, Mol. Cell. Biochem, 178 (1-2): 77-80).
Thus, the difference in peroxide sensitivity, as we suggested and it is consistent with others, is due to Ca2+-independent mechanism(s) that involved in ET-1 mediated contraction in coronary artery smooth muscle which appears to be resistence to peroxide damage.

Mon Dec 7