Total cellular RNA was isolated using TRIZOL reagent (Life Technologies). For reverse transcription, each sample containing 10 μg of total RNA, 50 mmol/L of Tris-HCl, pH 8.3, 75 mmol/L of KCl, 0.5 mmol/L of MgCl2, 10 mmol/L of dithiothreitol, 0.5 nmol/L each deoxynucleoside triphosphate, 20 U of ribonuclease inhibitor, 100 pmol/L of random hexamer, and 200 U of reverse transcriptase (RT) in a final volume of 33 μL was incubated at 37°C for 1 h. For polymerase chain reaction (PCR), each sample containing 50 pmol upstream and downstream primers (glyceraldehyde phosphated dehydrogenase [GAPDH]-F38, 5′-GCGCCTGGTCACCAGGGCTGCTT-3′ and GAPDH-R502, 5′-TGCCGAAGTGGTCGTGGATGACCT-3′, 465 base-pair, gene ID: 49387614–; SERCA-F2773, 5′-AAGCAGTTCATCCGCTACCT-3′ and SERCA-R2906, 5′-AGACCATCCGTCACCAGATT-3′, 134 base-pair, gene ID: 2906; PLB-F189, 5′-TACCTTACTCGCTCGGCTATC-3′ and PLB-R329, 5′-CAGAAGCATCACAATGATGCAG-3′, 141 base-pair, gene ID: 6467215), 200 nmol/L deoxynucleoside triphosphate, 50 mmol/L KCl, 10 mmol/L Tris-HCl, pH 8.3, 10 mmol/L MgCl2, 2.5 U Taq DNA polymerase in a final volume of 50 μL was amplified for 21 (GAPDH), 26 (SERCA) or 24 (phospholamban) cycles. The amplification profile involved denaturation at 94°C for 45 s, primer annealing at 52°C (GAPDH), 55°C (SERCA) or 53°C (PLB) for 45 s and primer extension at 74°C for 45 s. After the last cycle, samples were incubated at 74°C for 15 min to extend incomplete products. The PCR product of GAPDH (5 μL) was mixed with SERCA (5 μL) or phospholamban (5 μL) and then was analyzed on 2% agarose gel and semiquantified using Kodak Digital Science 1D 2.0 imaging software. The PCR product of GAPDH was detected as a 465 base-pair band, SERCA as a 134 base-pair band and phospholamban as a 141 base-pair band according to the marker.