caa a22 4500 477119328 CHVBK 20180405111631.0 cr unu---uuuuu 170330e19960301xx s 000 0 eng 10.1007/BF00240044 doi (NATIONALLICENCE)springer-10.1007/BF00240044 Effects of hypoxia, simulated ischemia and reoxygenation on the contractile function of human atrial trabeculae [Elektronische Daten] [Andreas Lammerich, Jürgen Bohm, Ingolf Schimke, Kay-Dietrich Wagner, Eberhard Storch, Joachim Günther] Hypoxia, ischemia and reoxygenation cause contractile dysfunction which will be characterized by the time course of isometric contraction of human atrial trabeculae. Post-rest potentiation (PRP) and postextrastimulatory potentiation (PEP) were elicited to obtain indirect information about the role of the sarcoplasmic reticulum (SR) in excitation-contraction coupling. As lipid peroxidation could cause SR dysfunction, thiobarbituric acid reactive substances (TBARS) were measured. After 30 min of hypoxia (H) or simulated ischemia (H combined with acidosis-SI), contractile force decreased to 15% and 6%, respectively, of control (p <- 0.05), whereas the normalized rate of both contraction and relaxation increased. In group H, rapid reoxygenation produced a recovery of contractile force to about 60%. After post-hypoxic reoxygenation the TBARS concentration was increased. In group SI, rapid reoxygenation and a rather gradual correction of acidosis produced complete recovery of contractile force. PRP and PEP were maintained during H and SI. Particularly post-ischemic reoxygenation caused a marked depression of PRP and partly of PEP. Thus, alteration of SR Ca2+ handling occurs predominantly during reoxygenation rather than during H or SI, probably associated with the damaging effect of increased oxygen radicals. The depression of potentiation occured along with delayed relaxation, temporary increased resting force, mechanical alternans, and spontaneous activity which are further characteristics for SR dysfunction. Thus, for a possibly beneficial effect of low pH during SI combined with its gradual correction during reoxygenation on the recovery of contractile function, developed force should not be the only index. Kluwer Academic Publishers, 1996 hypoxia nationallicence simulated ischemia nationallicence reoxygenation nationallicence contractile function nationallicence human atrial trabeculae nationallicence Lammerich Andreas Institute of Physiology, Humboldt-University, Tücholsky Str. 2, D-10117, Berlin, Germany aut Bohm Jürgen Clinic of Cardiac Surgery, Humboldt-University, Schumannstr 20-21, D-10098, Berlin, Germany aut Schimke Ingolf Clinic of Internal Medicine I, Humboldt-University, Schumannstr 20-21, D-10098, Berlin, Germany aut Wagner Kay-Dietrich Institute of Physiology, Humboldt-University, Tücholsky Str. 2, D-10117, Berlin, Germany aut Storch Eberhard Institute of Physiology, Humboldt-University, Tücholsky Str. 2, D-10117, Berlin, Germany aut Günther Joachim Institute of Physiology, Humboldt-University, Tücholsky Str. 2, D-10117, Berlin, Germany aut Molecular and Cellular Biochemistry Kluwer Academic Publishers; http://www.wkap.nl 160-161/1(1996-03-01), 143-151 0300-8177 160-161:1<143 1996 160-161 11010 https://doi.org/10.1007/BF00240044 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00240044 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Lammerich Andreas Institute of Physiology, Humboldt-University, Tücholsky Str. 2, D-10117, Berlin, Germany aut NATIONALLICENCE 700 1- Bohm Jürgen Clinic of Cardiac Surgery, Humboldt-University, Schumannstr 20-21, D-10098, Berlin, Germany aut NATIONALLICENCE 700 1- Schimke Ingolf Clinic of Internal Medicine I, Humboldt-University, Schumannstr 20-21, D-10098, Berlin, Germany aut NATIONALLICENCE 700 1- Wagner Kay-Dietrich Institute of Physiology, Humboldt-University, Tücholsky Str. 2, D-10117, Berlin, Germany aut NATIONALLICENCE 700 1- Storch Eberhard Institute of Physiology, Humboldt-University, Tücholsky Str. 2, D-10117, Berlin, Germany aut NATIONALLICENCE 700 1- Günther Joachim Institute of Physiology, Humboldt-University, Tücholsky Str. 2, D-10117, Berlin, Germany aut NATIONALLICENCE 773 0- Molecular and Cellular Biochemistry Kluwer Academic Publishers; http://www.wkap.nl 160-161/1(1996-03-01), 143-151 0300-8177 160-161:1<143 1996 160-161 11010 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer