Figure 5

Comparison of GIRK1 mRNA expression levels by relative competitive RT-PCR in MDA-MB-453 cells treated with propranolol for 30 minutes daily for 7 days. Propranolol (1 μM) was added daily for seven days and then removed after 30 minutes. cDNA was amplified by PCR using GIRK1 primers and 18S primers/competimers. Lanes 1–5) untreated control; Lanes 6–10) propranolol treated cells; Lane 11) untreated control, RT reaction without MMLV; Lane 12, MDA-MB453 treated with propranolol, RT reaction without MMLV. Densitometry values were determined using the phosphoimager. Densitometry Girk 1/ Densitometry 18S-control-0.6055 ± 0.0685 (SD); propranolol treated 0.5636 ± 0.0611 (SD). The bands were consistent with the expected sizes, 441 bp for the GIRK 1 primers and 324 bp for the 18S primers/competimers.