Abstract
Aims:
Ischemia/reperfusion injury (I/R) is one of the early factors of endothelial-cell-damage and seems to be an important risk factor for chronic rejection following heart transplantation. Free oxygen radicals formed during I/R play a major role of endothelial-cell-damage. Ubiquinone Q is a crucial component of the mitochondrial transport chain and an antioxidant. The aim of this study was to proveif and to which extent I/R has an effect of the concentration of Ubiquinone Q as an important antioxidant protect-system in rat heart after heterotopic rat heart transplantation.
Methods:
Lewis to F344 heterotopic rat heart transplantation was performed. Donor and recipient were anesthetized with isofluran per inhalation. Cold ischemia was extended to 30min or 480min 4°C, respectively. Cardiac allografts were harvest after 70 days or rather after 140 days. Identification and quantification of Q9+Q10 in transplanted and recipient rat heart homogenates were detected by HPLC. mRNA levels of Q9+Q10 were analyzed by real time PCR.
Results:
We could found a distinct reduction of Q9+Q10 in transplanted heart homogenate in comparison to recipient rat heart using HPLC. Additionally there was a significantly more reduction in these animals compared to control rats. mRNA expression levels of Q9+Q10 in cardiac allografts comfirmed the HPLC results.
Conclusions:
Ubiquinone Q9+Q10 are significantly decreased in transplanted rat heart but there was no difference in regulation of Ubiquinone Q9+Q10 concerning effects of I/R. Further investigation should be focus on the influence of the reduction of Ubiquinone in the development for chronic cardiac allograft vasculopathy.