Figure 6. Molecular identification of SK1 and SK3 channel mRNA in porcine brain and PEG cells.

A, PCR products (40 cycles) obtained from RT-PCR reactions performed using cDNA synthesized from DNase-treated mRNA isolated from porcine brain (primers are described in the Methods). Control: no RT reactions were performed using RNA instead of cDNA for each primer set. In the no template (nT) control, molecular biology grade water was used to replace the cDNA template. B, SK channel expression in immortalized PEG cells. SK1 and SK3 PCR products were detected at 40 cycles. Similar control reactions were performed as described in A. C and D, treatment with 20 nm oestradiol-17β for 4 days resulted in a 2.3-fold increase in SK3 mRNA expression and a 1.9-fold decrease in SK1 mRNA expression compared to serum-free controls as indicated by densitometry analysis (29 and 38 cycles, respectively). No difference in GAPDH mRNA expression was detected between serum-free and oestradiol-17β-treated monolayers.