MR silencing in transgenic mice.

<p>Control (con) and transgenic (tg) mice of line B and D received Dox via food pellets for 14 days or, in some cases, were left untreated (w/o). (A) Whole kidneys were analyzed for MR mRNA expression by RT-QPCR. N = 14/22 (Dox, line B), N = 5/7 (w/o, line B), N = 13/20 (Dox, line D), N = 5/6 (w/o, line D). (B) Whole hearts were analyzed for MR mRNA expression by RT-QPCR. N = 9/17 (Dox, line B), N = 5/7 (w/o, line B), N = 13/14 (Dox, line D), N = 6/7 (w/o, line D). Gene expression in panels A and B was normalized to HPRT; mRNA levels in control mice were arbitrarily set to 1 and are depicted as mean ± SEM. (C) Protein lysates were prepared from kidney and heart of Dox-treated mice of line B and analyzed by western blot for the amount of MR protein. Detection of ERK served as a loading control. One representative analysis each is depicted in the left panel. The right panel shows a densitometric quantification of MR in kidney and heart of control (con) and transgenic (tg) mice after normalization to the amount of ERK. Protein levels are depicted in arbitrary units as mean ± SEM. N = 5/6. (D) Colon, hippocampus, liver, lung, stomach and muscle were isolated from Dox-treated mice of line B and analyzed for MR mRNA levels by RT-QPCR. Gene expression was normalized to HPRT and is depicted in arbitrary units as mean ± SEM. N = 4/7. Statistical analysis in all panels was performed by unpaired two-tailed Student’s t test. n.s.: non-significant; *: p <0.05; **: p <0.01; ***: p <0.001.