Medizinische Universität Graz Austria/Österreich - Forschungsportal - Medical University of Graz
Gewählte Publikation:
Pierer, E.
Creating a prevascularized site for islet transplantation in rates
[ Dissertation ] Medical University of Graz; 2008.
- Autor*innen der Med Uni Graz:
- Betreuer*innen:
- Iberer Florian
- Maier Alfred
- Altmetrics:
- Abstract:
- Introducion: Naturally, islet cells are highly vascularized in the pancreas. This physiological vessel structure is damaged during the isolation process. Therefore, isolated islet cells dependent on diffusion of oxygen and nutrients form the surrounding tissue. After transplantation a lot of freshly isolated islet cells become apoptotic because of hypoxia. Thus, insulin independency can not be achieved because of graft dysfunction. The aim of the study was to show, that it is feasible to create a prevascularized site in rats, using a V.A.C (Vacuum Assisted Closure) GranuFoamTM, that is normally used in wound healing and HBO (hyperbaric oxygenation) to induce angiogenesis. Methods: 40 Sprague-Dawley rats are divided in 5 groups and the V.A.C.-GranuFoam is implanted in the subcutaneous tissue. According to the V.A.C.-Therapy, drainage is implanted in the subcutaneous tissue. According to the V.A.C.-GranuFoam HBO is administered to the different groups at different time-points for at least one week after implantation to a maximum 1 week prior and 3 weeks after implantation. After the experiments, the blood flow is measured using Szinitgraphy. Moreover the V.A.Cc-GranuFoam is explanted and processed for histology and immunohistochemistry to assess angiogenesis. Results: It sis feasible to create a prevascularized site in the subcutaneous fatty tissue of rats, using a V.A.C.-GranuFoam and HBO. Angiogenesis is not induced without HBO within one month after implantation of V.A.C.-GranuFoam but within 2 weeks after implantation of the system and HBO therapy. Vessels are not only distributed in GranuFoam is pervaded by new vessels. HBO therapy prior to the implantation does not have a significant influence on vessel growth. Conclusion: As ischemically damaged islets are likely to undergo cell death of loose functionality due to hypoxia, the use of the V.A.C.-GranuFoam and HBO might be a promising method to create a prevascularized site to achieve better results in islet transplantation.