Up-regulation of endothelin-converting-enzyme mRNA expression following XXXX .

@entity70578 @entity1827 @entity37909 @entity1167 @entity35 @entity1828
@entity1827 ( @entity1827 ) is believed to play an important role in cardiac ischaemia/reperfusion injury. @entity1827 is synthesized from preproET-1 by the action of @entity1828 ( @entity1828 ). It is unclear to what extent the ET system is activated following prolonged ischaemia. In this study we used a model mimicking the conditions of the donor heart during transplantation. Isolated @entity35 hearts perfused with Krebs-Henseleit buffer were subjected to 30 min of normothermic perfusion, then 4 h of @entity1167 at 4 degrees C with St Thomas' Hospital solution, followed by reperfusion for 2 h. Hearts were freeze-clamped at different time points during the protocol. Using quantitative reverse transcription-PCR, relative levels of @entity70578 mRNA expression were measured and compared with a housekeeping gene ( @entity37909 ). During reperfusion there was a consistent decrease in coronary flow to approx. 85-90% of pre-ischaemic flow. There was no significant alteration in preproET-1 mRNA expression during 2 h of reperfusion. However, @entity1828 mRNA expression was increased by 77.5% at 1 h and by 74.6% at 2 h following ischaemia compared with pre-ischaemic values (P<0.05). Thus we conclude that @entity1828 mRNA expression is increased following prolonged hypothermic @entity1167 . Elevations in the expression of this enzyme may help to explain the role of the ET system in the pathogenesis of ischaemia/reperfusion injury following cardiac surgery and transplantation.
