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Because the vagus nerve is implicated in control of inflammation, we investigated if brain death (BD) causes impairment of the parasympathetic nervous system, thereby contributing to inflammation. BD was induced in rats. Anaesthetised ventilated rats (NBD) served as control. Heart rate variability (HRV) was assessed by ECG. The vagus nerve was electrically stimulated (BD + STIM) during BD. Intestine, kidney, heart and liver were recovered after 6 hours. Affymetrix chip-analysis was performed on intestinal RNA. Quantitative PCR was performed on all organs. Serum was collected to assess TNF alpha concentrations. Renal transplantations were performed to address the influence of vagus nerve stimulation on graft outcome. HRV was significantly lower in BD animals. Vagus nerve stimulation inhibited the increase in serum TNF alpha concentrations and resulted in down-regulation of a multiplicity of pro-inflammatory genes in intestinal tissue. In renal tissue vagal stimulation significantly decreased the expression of E-selectin, IL1 beta and ITGA6. Renal function was significantly better in recipients that received a graft from a BD + STIM donor. Our study demonstrates impairment of the parasympathetic nervous system during BD and inhibition of serum TNF alpha through vagal stimulation. Vagus nerve stimulation variably affected gene expression in donor organs and improved renal function in recipients.

Background. Brain death and cold preservation are major alloantigen-independent risk factors for transplantation Outcome. The present study was conducted to assess the influence of these factors on transplantation-associated injury independently or in combination.Methods. Brain death was induced in F344 rats. Renal grafts were harvested after 6 hr and either directly transplanted in unilateral nephrectomized Lewis recipient or Subjected to 24 hr of cold preservation in University of Wisconsin solution before implantation. Allografts obtained from living donor rats were also subjected to cold preservation or not. DNA damage was assessed before implantation by terminal deoxynucleotide transferase-mediated dUTP nick-end labeling staining. Ten days after transplantation, renal histology was performed according to Banff '97 classification. The expressions of cytokines and adhesion molecules were analyzed by quantitative polymerase chain reaction.Results. Cold preservation significantly increased the number of terminal deoxynucleotide transferase-mediated dUTP nick-end labeling positive cells in renal allografts. Ten days after transplantation, histology revealed a higher degree of tubulitis and vasculitis scores when the grafts were Subjected to cold storage. Vasculitis was aggravated when the graft was obtained from brain death (BD) donors. BD, but not cold preservation alone, was associated with papillary necrosis. This was more frequently observed after cold preservation. Immunohistology showed an increase in MHC class II+ cells after cold preservation. The combination of BD and cold preservation revealed a higher degree of VEGF and IL-10 expression.Conclusions. Our Study emphasizes that cold ischemia time should be limited when renal allografts from brain-dead donors are transplanted.