New cardiac expression of two adenosine-2A receptor isoforms in dysfunctioning minipigs

AbstractPurpose: Eight A2AR variants are reported in humans while no A2AR isoforms in pigs. The aim of this study was to evaluate potential isoforms presence in cardiac pig tissue to better define possible involvement of A2AR in the cardiovascular pathophysiology.Materials and methods: In adult male minipigs (n = 4) left ventricular dysfunction (LVD) was induced by pacing at 200 bpm in the right ventricular (RV) apex. In these animals and in sham operated pigs (C-SHAM, n = 4) cardiac tissue was collected from LV-septal wall (LV-SW)-close to pacing site-and from lateral (opposite) site (LV-OSW). A2AR specific primers, derived from Sus scrofa AY772412 sequence, were used for Real-Time PCR. The DNA was sequenced using the Sanger method. Histological analysis was also performed.Results: In LV-SW of LVD minipigs the A2AR melting curves were characterized by a sharp peak between 87 and 91 °C (short isoform, 1–94 bp) on the right of the principal peak corresponding to a long A2AR isoform (GenBank: JQ229674.1) 1–...