Acute T3 treatment protects the heart against ischemia-reperfusion injury via TR alpha 1 receptor

作者：Pantos Constantinos^*; Mourouzis Iordanis; Saranteas Theodosios; Brozou Vassiliki; Galanopoulos Georgios; Kostopanagiotou Georgia; Cokkinos Dennis V

来源：Molecular and Cellular Biochemistry, 2011, 353(1-2): 235-241.

DOI：10.1007/s11010-011-0791-8

• Thyroid hormone
• Thyroid hormone receptors
• Myocardial ischemia
• Acute myocardial infarction
• Cardiac surgery

We have previously shown that acute thyroid hormone treatment could limit reperfusion injury and increase post-ischemic recovery of function. In the present study, we further explore potential initiating mechanisms of this response. Thus, isolated rat hearts were subjected to 30 min zero-flow global ischemia (I) followed by 60-min reperfusion (R). Reperfusion injury was assessed by post-ischemic recovery of left ventricular developed pressure (LVDP%) and LDH release. T3 at a dose of 60nM which had no effect on contractile function of non-ischemic myocardium, significantly increased LVDP% [48% (2.9) vs. 30.2% (3.3) for untreated group, P < 0.05] and reduced LDH release [8.3 (0.3) vs. 10 (0.42) for untreated group, P < 0.05] when administered at R. T4 (60 and 400 nM) had no effect on contractile function either in non-ischemic or ischemic myocardium. Administration of debutyl-dronedarone (DBD), a TR alpha 1 antagonist abolished the T3-limiting effect on reperfusion injury: Thus, co-administration of T3 and DBD resulted in significantly lower LVDP%, [23% (4.7) vs. 48% (2.9) for T3 group, P < 0.05] and higher LDH release [9.9 (0.3) vs. 8.3 (0.3), for T3 group, P < 0.05]. In conclusion, acute T3 and not T4 treatment will be able to protect against reperfusion injury. T3 can exert this beneficial effect on ischemic myocardium at a dose that has no effects on non-ischemic myocardium. Acute T3-limiting effect on reperfusion injury is mediated, at least in part, via TR alpha 1 receptor.

• 出版日期2011-7