caa a22 4500 477119603 CHVBK 20180405111632.0 cr unu---uuuuu 170330e19960301xx s 000 0 eng 10.1007/BF00240041 doi (NATIONALLICENCE)springer-10.1007/BF00240041 Biphasic changes in relaxation following reperfusion after myocardial ischemia [Elektronische Daten] [Susana Mosca, Martín Carriquiriborde, Horacio Cingolani] The present study provides evidences of left ventricular diastolic alterations following reperfusion in a model of global ischemia. Isolated perfused rabbit and rat hearts, were subjected to ischemia for 15 and 20 min respectively, followed by 30 min of reperfusion. In rabbit heart at the end of the reperfusion period, isovolumic left ventricular developed pressure (LVDP) and +dP/dtmax stabilized at 55 ± 3% and 60 ± 2% of preischemic values respectively and, in rat heart LVDP = 61 ± 8% and +dP/dtmax = 57 ± 9% of preischemic values. Stunned heart was then obtained from both species. Left ventricular end diastolic pressure (LVEDP) values stabilized at the end of reperfusion period at values higher than preischemic conditions in both species (38.9 ± 4.4 mmHg and 30.3 ± 3.1 mmHg in rabbit and rat respectively). The time constant of relaxation (T) increased early in reperfusion in both species, but then decreased and stabilized at the end of reperfusion period at values lower than preischemic values. The ratio between both maximal velocities (+P/-P), also showed a transitory impairment in relaxation, followed by normalization and stabilization at values lower than preischemic values. This biphasic pattern in relaxation was detected in both species. The changes in relaxation were dissociated from the diastolic compliance and could be the result of a transitory calcium overload and/or sarcoplasmic reticulum dysfunction. The faster myocardial relaxation at the end of reperfusion period is consistent with the decreased myofilament sensitivity, which characterizes the stunned myocardium. Kluwer Academic Publishers, 1996 myocardial stunning nationallicence diastolic stiffness nationallicence myocardial relaxation nationallicence Mosca Susana Centro de Investtgaciones Cardiovasculares, Universidad Nacional de La Plata, 60 y 120, 1900, La Plata, Argentina aut Carriquiriborde Martín Centro de Investtgaciones Cardiovasculares, Universidad Nacional de La Plata, 60 y 120, 1900, La Plata, Argentina aut Cingolani Horacio Centro de Investtgaciones Cardiovasculares, Universidad Nacional de La Plata, 60 y 120, 1900, La Plata, Argentina aut Molecular and Cellular Biochemistry Kluwer Academic Publishers; http://www.wkap.nl 160-161/1(1996-03-01), 123-128 0300-8177 160-161:1<123 1996 160-161 11010 https://doi.org/10.1007/BF00240041 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00240041 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Mosca Susana Centro de Investtgaciones Cardiovasculares, Universidad Nacional de La Plata, 60 y 120, 1900, La Plata, Argentina aut NATIONALLICENCE 700 1- Carriquiriborde Martín Centro de Investtgaciones Cardiovasculares, Universidad Nacional de La Plata, 60 y 120, 1900, La Plata, Argentina aut NATIONALLICENCE 700 1- Cingolani Horacio Centro de Investtgaciones Cardiovasculares, Universidad Nacional de La Plata, 60 y 120, 1900, La Plata, Argentina aut NATIONALLICENCE 773 0- Molecular and Cellular Biochemistry Kluwer Academic Publishers; http://www.wkap.nl 160-161/1(1996-03-01), 123-128 0300-8177 160-161:1<123 1996 160-161 11010 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer