We determined mRNA expression of genes of endothelin-1 (ET-1), and of the transforming growth factor beta ligands (TGFβ1, TGFβ2 and TGFβ3), their receptors (TβRI and TβRII) and their pseudoreceptor BAMBI in the heart of broilers raised under cold temperature conditions and affected by pulmonary hypertension. Gene expression was determined by RT-qPCR in right myocardial ventricle samples from 4-week-old chickens (n = 48) raised either under normal (control) or cold temperature conditions (22 °C versus 14 °C). We do not find differences among healthy birds, birds with cardiac failure and ascitic birds in the mRNA levels of TGFβ2, TGFβ3 and BAMBI. In the control group, ET-1 mRNA level was increased in the ascitic birds as compared with healthy birds and birds with cardiac failure (p < 0.05) whereas in the cold treated group, no increase was observed (p > 0.05); yet, ascitic birds in the cold group showed lower mean than ascitic birds in the control group (p < 0.05). TβRII mRNA expression was higher in ascitic than in healthy birds (p < 0.05) in both control and cold treated groups; however, in the ascitic birds of the cold treated group TβRII expression was lower than in ascitic birds from the control group (p < 0.05). Thus, the higher ET-1 and TβRII levels observed in ascitic birds seem to be attenuated by cold.
Keywords: Heart failure; ascites syndrome; extracellular matrix; myocardial remodeling.