Genetic expression profile of non-ischaemic remote myocardium: very acute and distinct changes in each ventricle.

• Type: Summary of Presentation in an International Conference
• Date: 2005

Authors

Guerra M (Author) Other; Lourenço AP (Author) FMUP; Roncon-Albuquerque R Jr (Author) FMUP; Falcão-Pires I (Author) FMUP; Leite-Moreira AF (Author) FMUP

Conference proceedings International

Title: European Journal of Heart Failure

Initial page: 119

ESC Annual Congress 2005

Stockholm, Sweden , 03 a 07 de Setembro de 2005

Scientific classification

FOS: Medical and Health sciences > Other medical sciences

Other information

Resumo (PT): Recently, we demonstrated a transient LV systolic dysfunction and a sustained RV and LV diastolic dysfunction with a change of the genetic expression of remote non-ischemic myocardium, after 120 min of LAD occlusion. Gene expression of NCX and SERCA2a were decreased and Phospholamban (PLB) mRNA was increased only in the LV; BNP, IGF-1, HIF-1a and inflammatory mediators as IL-6 and iNOS were increased in both ventricles. The objectives of the present study were to determine the precocity of the genetic changes of remote myocardium and to understand the distinct genetic modulation of each ventricle after a period of 30 min of ischemia. Wistar rats instrumented with RV and LV tip micromanometers randomly underwent either LAD coronary artery ligation (n=7) or sham procedures (n=7) during 30 min. Hemodynamic parameters were recorded continuosly and transmural samples of RV and LV remote myocardium were collected for relative quantification of mRNA of ET-1, IGF-1, NCX, SERCA2a, PLB, NHE, HIF-1a, BNP, IL-6, iNOS and TNF-a by real-time RT-PCR. Evan’s blue infusion after LAD occlusion in 5 additional rats revealed reproducible areas of antero-apical LV and left IV septal ischemia (41±5.4% of LV+IV septum weight). In remote myocardium we observed an increase of genetic expression of: (I) IGF-1 (LV: 567±192% and RV: 59±18%) and HIF-1a (LV: 190±94% and RV: 63±25%) in both ventricles; (II) BNP (567±192%) e IL-6 (977±568%) only in the LV; and (III) iNOS (256±88%) only in the RV. We still observed a significantly decrease in mRNA of NHE (79±5%) in the RV and a tendency to a decrease of expression of calcium regulatory protein SERCA2a (44±10%, p=0,10) in the LV. The genetic changes in remote non-ischemic myocardium observed after 120 min of LAD occlusion, as well as, the distinct modulation of each ventricle are already present at 30 min. This very acute genetic modulation after LV ischemia takes place not only in the LV but also in the non-ischemic RV. This modulation assumes distinct features in the two ventricles possibly due to distinct mechanical and inflammatory stresses, as well as, to intrinsic myocardial properties of the RV and the LV. The remarkable activation of cytokines and growth factors may contribute to the functional disturbances in this setting.

Language: English

Type (Professor's evaluation): Scientific

Notes: 27th Congress of the European-Society-of-Cardiology, published in journal, European Heart Journal. 2005; Vol.26(Abstract.851)(Suppl1):119-119.