and RNA was reverse transcribed to single-stranded cDNA using a High Capacity Kit
(Applied Biosystems, USA) according to the manufacturer's protocol. For quantitative
analysis of the genes of interest [pre-pro-AM (Rn 00562327_m1), CRLR (Rn
00562334_m1), RAMP1 (Rn 01427056_m1), RAMP2 (Rn 00824652_m1), and RAMP3 (Rn
00571815_m1)], a commercially available TaqMan Assay-on-Demand System that consists
of a kit of oligonucleotides and probes was used (Applied Biosystems). Reverse
transcription was performed using 1 µg total RNA for each sample in 20 µL of the
total reaction mixture. The cDNA obtained was diluted 1:10, and 4.5 µL was used for
each 10 µL of the qRT-PCR mixture using the TaqMan Master Mix (Applied Biosystems).
Reactions were carried out in duplicate and analyzed with 7500 Sequence Detection
System apparatus (Applied Biosystems). Data were analyzed using the ABI-7500 SDS
software (Applied Biosystems). Total RNA absorbed was normalized on the basis of the
Ct value for the GAPDH gene (Rn 01775763_m1). The variation in expression among
samples was calculated by the 2−ΔΔCt method, and the mean delta Ct value
for a group of six samples from the control was used for calibration (17 (link)).