Objective  To evaluate the effect of hypothermic machine perfusion (HMP) on the expression levels of inflammatory cytokines in rat kidney.

  Methods  Thirty male rats were randomly divided into the control (Control group), static cold storage group (SCS group) and HMP group, with 10 rats in each group. The velocity, intrarenal resistance and pH value of perfusion effluent were recorded during HMP. The expression levels of CXC chemokine ligand (CXCL)1, CXCL2, interferon (IFN)-β1, IFN-α4, CC chemokine ligand (CCL)2, CCL20, interleukin (IL)-17α, IL-17C and tumor necrosis factor (TNF)-α messenger RNA (mRNA) in renal tissues were evaluated by reverse transcription polymerase chain reaction (RT-PCR). Pathological changes of the kidney were observed by hematoxylin-eosin (HE) staining.

  Results  During HMP, the velocity and intrarenal resistance remained stable, and the pH value of perfusion effluent was decreased slowly. RT-PCR showed that the relative expression levels of CXCL1, CXCL2, CCL2, CCL20, IL-17α, IL-17C and TNF-α mRNA in the SCS and HMP groups were higher compared with those in the Control group. Compared with the SCS group, the relative expression levels of CXCL1, CXCL2, CCL2, CCL20, IL-17α and TNF-α mRNA were up-regulated in the HMP group (all P<0.05). HE staining revealed that the morphology of renal cells was normal in the Control group, whereas evident epithelial necrosis, cytoplasmic vacuolation, brush border loss and epithelial shedding were observed in the SCS group. Compared with the SCS group, pathological changes in the HMP group were alleviated.

  Conclusions  HMP may activate renal inflammation, and inhibiting the activation of inflammation during HMP is expected to further improve the effect of allograft preservation.