Effect of thyroid hormone on cardiac function in the ischemia/reperfusion injury of wistar rats. Role of AT2 receptor and AMPK signaling pathway.

Author(s)

Felix Meira Tavares

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI)
• Defense date: 2012-03-30

Examining board members

Maria Luiza Morais Barreto de Chaves; Vagner Roberto Antunes; Dalton Valentim Vassallo

• Advisor: Maria Luiza Morais Barreto de Chaves

Abstract

Thyroid Hormones (TH) is a phenotype of cardioprotection and may influence the trophic state of cardiac tissue through several mechanisms, including the modulation of the components of renin-angiotensin system - angiotensin II and its receptors (AT1 and AT2). The present study aimed to evaluate the role of AT2 receptor in cardioprotection mediated by the TH and the involvement of AMP-activated protein kinase (AMPK) in this context. A model of Ischemia and Reperfusion (I/R) was performed in isolated hearts of rats subjected to experimental hyperthyroidism, in the presence or absence of the AT2 receptor antagonist (PD123319), using the Langendorff system. The results showed that TH exerts cardioprotective effect with increased levels of AT2 and phosphorylated AMP protein expression, which was prevented by the administration of PD, with a loss in cardiac function. These data suggest that part of the TH-induced cardioprotection is mediated by the AT2 receptor with the involvement of AMPK in protection of the myocardium after I/R injury. (AU)

• FAPESP's process: 10/00933-9 - Effect of Thyroid Hormone on cardiac function in the Ischemia/Reperfusion injury of Wistar rats. Role of AT2 receptor and AMPK signaling pathway.
• Grantee: Felix Meira Tavares
• Support Opportunities: Scholarships in Brazil - Master