Abstract | OBJECTIVE:
Corticosteroids and hyperoxia protect the heart against ischemia-reperfusion injury and may attenuate vascular reactivity. We hypothesized that (1) combining these two pretreatments induces an additive cardioprotection, (2) protection depends on activation of survival kinases and/or heat shock proteins, and (3) these interventions would change vascular reactivity into a more relaxed state. METHODS: RESULTS:
Infarct size was attenuated in all pretreated groups versus controls: 29% reduction in the combined group (p<0.01), 23% in hyperoxia group (p<0.05) and 31% in dexamethasone group (p<0.01). There was no significant difference between the treated groups. Combined pretreatment improved postischemic left ventricular end diastolic pressure compared to all other groups (p<0.001 vs controls, p=0.002 vs dexamethasone, p=0.005 vs hyperoxia). Combined pretreatment improved left ventricular developed pressure and coronary flow compared to controls (p<0.001 for both) and hyperoxia (p=0.0047 and p=0.0024, respectively). Combined pretreatment enhanced endothelium-independent relaxation (p=0.0032) compared to controls. Excepting ERK1/2 phosphorylation in the combined group during early reperfusion, there was no increased phosphorylation of the survival kinases AKT, p38, JNK, or AMPK and no increase of HSP72 expression. CONCLUSION:
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Authors | Mari-Liis Kaljusto, Kåre-Olav Stensløkken, Tomohisa Mori, Andrey Panchenko, Marthe-Lise Frantzen, Guro Valen, Jarle Vaage |
Journal | European journal of cardio-thoracic surgery : official journal of the European Association for Cardio-thoracic Surgery
(Eur J Cardiothorac Surg)
Vol. 33
Issue 3
Pg. 355-63
(Mar 2008)
ISSN: 1010-7940 [Print] Germany |
PMID | 18221880
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Adrenal Cortex Hormones
- HSP72 Heat-Shock Proteins
- Dexamethasone
- Phosphotransferases
- Protein Kinases
- Proto-Oncogene Proteins c-akt
- JNK Mitogen-Activated Protein Kinases
- Mitogen-Activated Protein Kinase 3
- AMP-Activated Protein Kinase Kinases
- Oxygen
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Topics |
- AMP-Activated Protein Kinase Kinases
- Adrenal Cortex Hormones
(therapeutic use)
- Animals
- Blood Pressure
(physiology)
- Dexamethasone
(pharmacology, therapeutic use)
- Enzyme Activation
- HSP72 Heat-Shock Proteins
(metabolism)
- Immunoblotting
- Ischemic Preconditioning, Myocardial
(methods)
- JNK Mitogen-Activated Protein Kinases
(metabolism)
- Male
- Mitogen-Activated Protein Kinase 3
(metabolism)
- Myocardial Reperfusion Injury
(metabolism, physiopathology, prevention & control)
- Myocardium
(metabolism)
- Oxygen
(administration & dosage)
- Phosphotransferases
(metabolism)
- Preoperative Care
(methods)
- Protein Kinases
(metabolism)
- Proto-Oncogene Proteins c-akt
(metabolism)
- Random Allocation
- Rats
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