Panel A, RT-PCR was conducted using RNA isolated from HL-1 cardiomyocytes with the use of primers designed for mouse STIM1 and Orai1 (expected sizes, 140 and 150 bp respectively). There was no significant amplification in the no-template control (NTC) or the no-reverse transcriptase (NRT; Taq polymerase only) samples (HW Lad= 100 bp ladder; LW Lad= 50 bp ladder). Panel B, Western blot using STIM1, Orai1, and β-tubulin antibodies and total protein isolated from HL-1 cardiomyocytes as well as a positive control (skeletal muscle).