*2.13. Gene Expression Analysis by RT*<sup>2</sup> *Profiler PCR Array*

Interlayers of the cryosectioned hearts were used for RNA-isolation, which was performed with TRIzol® reagent. Reverse transcription as well as PCR were performed using RT2 Profiler PCR Array Mouse Angiogenesis® kit (Qiagen, Germantown, MD, USA). According to the instructions of the manufacturer an RT<sup>2</sup> SYBR Green ROX qPCR Mastermix (Qiagen) was used. The expression of the housekeeping genes *ActB*, *B2M*, *GAPDH*, *GUSB*, and *HSP90AB1* as well as the gene panel were analyzed in triplicates and normalized to the mean of all the housekeeping genes. No genomic DNA was found in the samples. Moreover, we observed no apparent inhibition by any impurities that affect the reverse transcription as well as the amplification of the gene-specific products.
