Sex differences in the effects of aging or hormone deficiency in cardiac stunning models

COLAREDA G; BONAZZOLA P; LOFEUDO, JM; DIAZ, RG; CONSOLINI AE

Mar del Plata

Congreso; Reunión Conjunta SAIC-SAB-AAFE-AACYTAL 2023; 2023

SOCIEDAD ARGENTINA DE INVESTIGACIÓN CLÍNICA (SAIC) - SOCIEDAD ARGENTINA DE BIOQUIMICA(SAB) - ASOCIACION ARGENTINA DE FARMACOLOGIA EXPERIMENTAL (AAFE)- ASOCIACION ARGENTINA DE CIENCIA Y TECNOLOGIA DE ANIMALES DE LABORATORIO (AACYTAL)

Age is a cardiac risk factor, and the post-menopausal stage equalsthe incidence of heart attack between both sexes. Although the estrogeniccardioprotective effect is known, especially for reducingcardiovascular risk factors, the studies carried out to date suggestthat protection against the ischemic event occurs specifically aftera longer ischemic time. On the other hand, whether testosterone isinvolved is uncertain, and whether age modifies responses to I/R isunclear. We investigated sex- and age-dependent differences in cardiacstunning. Methods: Hearts of female (F) and male (M) youngrats (5 months old) gonadectomized (OVX, GDX) or not (YF, YM)and aging rats (over 20 months old, AgF, AgM) were isolated andperfused with Krebs solution under stimulation in a flow calorimeter.Once stabilized, a period of 20 min I and 45 min R was generated.Intraventricular pressure (LVP, mmHg) and heat rate (Ht, mW/g)were simultaneously measured. Maximum developed pressure (P),diastolic pressure (LVEDP) and muscle economy (ECO=P/Ht) werecalculated. Serum testosterone and estradiol levels were measuredwith ELISA assays. Results: AgF had less postischaemic contractilerecovery (PICR) (48.02±4.6% of initial P) than YF (78.2±2.8%,p