gms | German Medical Science

128. Kongress der Deutschen Gesellschaft für Chirurgie

Deutsche Gesellschaft für Chirurgie

03.05. - 06.05.2011, München

Tetrahydrobiopterin protects pancreatic grafts from ischemia-reperfuson-injury: Does the endothelial nitric oxide synthase play a role?

Meeting Abstract

  • Benno Cardini - Medizinische Universität Innsbruck, Division of Biological Chemistry, Innsbruck
  • Gerald Brandacher - Universitätsklinik Innsbruck, Department of Visceral, Transplant and Thoracic Surgery, Innsbruck
  • Martin Hermann - Universitätsklinik Innsbruck, Department for Islet Cell Transplantation, Innsbruck
  • Katrin Watschinger - Medizinische Universität Innsbruck, Division of Biological Chemistry, Innsbruck
  • Rupert Oberhuber - Universitätsklinik Innsbruck, Department of Visceral, Transplant and Thoracic Surgery, Innsbruck
  • Peter Obrist - St. Vinzenz KH, Institute of Pathology, Zams
  • Raimund Margreiter - Universitätsklinik Innsbruck, Department of Visceral, Transplant and Thoracic Surgery, Innsbruck
  • Johann Pratschke - Universitätsklinik Innsbruck, Department of Visceral, Transplant and Thoracic Surgery, Innsbruck
  • Ernst R. Werner - Medizinische Universität Innsbruck, Division of Biological Chemistry, Innsbruck
  • Manuel Maglione - Universitätsklinik Innsbruck, Department of Visceral, Transplant and Thoracic Surgery, Innsbruck

Deutsche Gesellschaft für Chirurgie. 128. Kongress der Deutschen Gesellschaft für Chirurgie. München, 03.-06.05.2011. Düsseldorf: German Medical Science GMS Publishing House; 2011. Doc11dgch441

DOI: 10.3205/11dgch441, URN: urn:nbn:de:0183-11dgch4410

Published: May 20, 2011

© 2011 Cardini et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.en). You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.


Outline

Text

Introduction: Ischemia-reperfusion-injury (IRI) following pancreas transplantation (PTX) is a major cause of graft pancreatitis. The essential cofactor of nitric oxide synthase (NOS) and potent antioxidant tetrahydrobiopterin (H4B) was shown to significantly attenuate IRI-induced graft pancreatitis. Since underlying mechanisms are still unclear, we investigated if the eNOS enzyme is the main target using an eNOS-/-model.

Materials and methods: In a heterotopic PTX model syngeneic C57Bl6 mice (wild type and eNOS-/-) served as donor-recipient pairs. Donors of both genotypes were either untreated or treated with 50 mg/kg b.w. H4B i.m. All grafts were subjected to 16 h cold ischemia time (CIT). Non-transplanted animals of both genotypes served as controls. Following 15 min and 2 h reperfusion, microcirculation was analyzed by confocal intravital fluorescence microscopy, parenchymal damage was assessed by H&E histology and nitrotyrosine immunostaining. Following 15 min reperfusion, microarray analysis (Affymetrix®) was performed and results were confirmed by RTqPCR (Taqman-technology).

Results: Prolonged CIT resulted in a pronounced microcirculatory breakdown, severe graft pancreatitis, as well as intragraft peroxynitrite formation. As early as 15 min following reperfusion no differences between treated and untreated grafts, and between genotypes were observed. After 2 h reperfusion time, H4B-treated grafts displayed a consistent amelioration of graft microcirculation (p=0.09). In addition, IRI-induced parenchymal damage and nitrotyrosine formation were reduced in treated grafts, reaching statistical significance only in wild types (p<0.05). Among the complete mouse genome two differently regulated genes (>5-fold) were detected by microarray analysis in grafts reperfused for 15 min, and confirmed by RTqPCR. Finally, H4B pre-treatment resulted in a significantly prolonged graft as well as recipient survival, indipendently from the donor genotype (p<0.001).

Conclusion: Comparable intraparenchymal damage of transplanted grafts and similar recipient survival in both genotypes if treated with H4B, suggest, that eNOS is not the major target of H4B in this model.