Ischemic postconditioning: differences between female and male

CALDIZ, CLAUDIA; FANTINELLI, JULIANA; ALEJANDRO CIOCCI PARDO; MARÍA S MOSCA

Congreso; 38th World Congress of the International Union of Physiological Sciences; 2017

Our objective was to determine the effects of ischemic postconditioning (IPC) on postischemic alterations in male (M) and female (F). The experiments performed with isolated hearts were: 1) Non-ischemic control (NIC): perfusion for 110 min; 2) Ischemic control (IC): 30-min global ischemia (GI) and 60-min reperfusion (R); 3) IPC: 3 cycles of 30 sec of GI and 30 sec of R at the beginning of R. Infarct size (IS) was measured. Systolic function was assessed by developed pressure of left ventricle (LVDP) and dP/dtmax; diastolic function by the -dP/dtmax and left ventricular end diastolic pressure (LVEDP). The expression of P-Akt, P-GSK-3β, and P-PKCε and superoxide production (SP), were determined at 3 min. of R. In IC, IS was lesser in F than M (29 ± 2 % and 40 ± 4 %, respectively, p < 0.05). At the end of R, LVDP, +dP/dtmax and -dPdtmax were higher in F than M (approximately 20 % and 55 %, respectively, p < 0.05). LVEDP was 26 ± 8 mmHg for F and 50 ± 4 mmHg for M (p < 0.05). The expression of phosphorylated kinases in NIC hearts was higher in F than M and its level increased in both sexes after GI-R. SP was lesser in F than M in all groups. After GI-R, SP increased in both sexes. IPC decreased IS and SP in F and M, improved the post-ischemic recovery of myocardial function and produced additional increase of kinases expression only in M.These results show that: 1.- IS was lesser and post-ischemic recovery of myocardial function was higher in F than M, 2.- The IPC decreased IS in both sexes but improved myocardial function after GI-R only in M. These differences could be attributed to a lesser SP and higher kinases activation in F than M.