il\VOLVEMENT OF RETII\OIC ACID II{ - MSpace at the University of ...

IL b.7. RAR alPha recePtor levels
The RAR alpha receptor levels were decreased to about 60Yoin response to 8 ¡rM
and 10 ¡rM adriamycin treatment when compared to the control. The treatment with 4 UM
adriamycin alone did not cause any change in the RAR alpha levels (Fig. 19), whereas
the treatment with antioúdant trolox in cells treated with 4 UM adriamycin resulted in
ZZo/o decrease in the RAR alpha receptor levels when compared to the control. There was
no adriamycin-induced decrease in the RAR receptor levels observed at 8 or 10 UM in the
presence of trolox (Fig. 19). 4 pM treated ADR group myocytes exhibited 121o/o
increase in the RAR alpha receptor levels when in the presence of 0.1 RA. However, at 8
and l0 ¡^lM adriamycin concentration the addition of 0.I pM of RA caused a significant
decrease in the RAR alpha receptors. Administration of I UM retinoic acid to the same
group caused significant increase in the RAR alpha receptor expression at all
concentrations of adriamYcin.
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