Direct visualization of leukocyte/endothelial cell interaction during extracorporeal circulation (ECC) in a new animal model
OBJECTIVE: The clinical complications of extracorporeal circulation(ECC) have been linked to a systemic activation of cellular and humoralcomponents and to a dysregulation of the microcirculatory compartment.Since to date only in vitro methods exist for evaluation, we developed ananimal model to stu...
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| Hauptverfasser: | , , , , |
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| Dokumenttyp: | Article (Journal) |
| Sprache: | Englisch |
| Veröffentlicht: |
01 May 1997
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| In: |
European journal of cardio-thoracic surgery
Year: 1997, Jahrgang: 11, Heft: 5, Pages: 973-980 |
| ISSN: | 1873-734X |
| DOI: | 10.1016/S1010-7940(97)01173-1 |
| Online-Zugang: | Verlag, lizenzpflichtig, Volltext: https://doi.org/10.1016/S1010-7940(97)01173-1
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| Verfasserangaben: | Markus Kamler, Heinz Jakob, Hans-Anton Lehr, Martha-Maria Gebhard, Siegfried Hagl |
| Zusammenfassung: | OBJECTIVE: The clinical complications of extracorporeal circulation(ECC) have been linked to a systemic activation of cellular and humoralcomponents and to a dysregulation of the microcirculatory compartment.Since to date only in vitro methods exist for evaluation, we developed ananimal model to study the effects of ECC on the microcirculation. Toestablish the model, we assessed whether these effects are dependent on theduration of ECC. METHODS: Intravital fluorescence microscopy was used onthe dorsal skinfold chamber preparation in chronically instrumented, awakeSyrian golden hamsters. ECC was realized using a micro-rollerpump and asilicon tube shunting blood between the carotid artery and the jugularvein. ECC was performed in three groups for various times (2, 10 and 20min) after application of heparin at 300 IU/kg body wt. In hamsters, theapplication of high-dose heparin releases endothelial bound superoxidedismutase (SOD), a natural scavenger of oxygen-derived free radicals.Protocol II assigned two groups receiving heparin at different doses of 50and 2000 IU/kg body wt. RESULTS: ECC for 2 min served as control to excludeeffects from hemodilution and resulted in a minimal induction ofleukocyte/endothelial cell interaction. Isovolemic ECC for 20 min resultedin an increase in rolling (from 11 +/- 3 to 38 +/- 20%, mean +/- S.D., P< 0.05) and adherent leukocytes (from 19 +/- 16 to 215 +/- 145cells/mm2, mean +/- S.D., P < 0.05) in postcapillary venules.Microhemodynamic parameters and functional capillary density were notsignificantly affected. Arterial blood pressure and heart rate were stable.Heparin at 2000 IU/kg inhibited post-ECC leukocyte adhesion following ECC,whereas 50 IU/kg showed no protective effects. CONCLUSIONS:Leukocyte/endothelial cell interaction, induced by blood contact withsynthetic surfaces, was directly visualized in vivo. The number of adherentleukocytes was dependent on the duration of ECC. The application ofhigh-dose heparin followed by release of SOD almost prevented leukocyteactivation, suggesting a formation of oxygen free radicals during ECC. Thenew application of the hamster model may allow to study the underlyingpathomechanisms and to develop therapeutic/prophylactic strategies to avertproblems associated with ECC. |
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| Beschreibung: | Gesehen am 10.06.2025 |
| Beschreibung: | Online Resource |
| ISSN: | 1873-734X |
| DOI: | 10.1016/S1010-7940(97)01173-1 |