Sirolimus delays recovery of rat kidney transplants after ischemia-reperfusion injury.
BACKGROUND
Sirolimus (SRL) seems to impair renal recovery from ischemic injury in animal models and delayed graft function after clinical renal transplantation. This study determined the impact of SRL on renal recovery after ischemia-reperfusion injury in a rat kidney transplant model.


METHODS
Syngeneic kidneys were preserved in University of Wisconsin solution before transplantation into bilaterally nephrectomized rats. Recipients received vehicle or SRL targeting for whole-blood trough levels of 10 to 20 ng/mL as measured by high-performance liquid chromatography. Renal function was assessed by animal survival or daily serum creatinine. Tissue samples were collected for histologic examination.


RESULTS
Median SRL whole-blood concentrations were 16.6 +/- 1.6 ng/mL on postoperative day (POD) 1 and 12.0 +/- 0.9 ng/mL on POD 3. Transplantation of kidneys after 39 hr of cold storage resulted in 30% survival in the SRL-treated group compared with 100% survival in the control group (P=0.002). Transplantation of kidneys after 24 hr of cold storage resulted in no survival differences, but there were significant differences in renal function. Daily serum creatinine (PODs 1-4) was higher in the SRL-treated group compared with the control group (P<0.05 at all time points). Grafts from SRL-treated animals showed more severe tubular necrosis compared with control animals.


CONCLUSIONS
When given at therapeutic immunosuppressive doses, SRL compromises renal function after ischemia-reperfusion injury in a rat kidney transplant model. The antiproliferative effect of SRL may translate into impairment of tubular repair and regeneration necessary for recovery after such injury.
Fuller
T Florian
TF
Department of Urology, Charité Hospital, Humboldt University Berlin, Berlin, Germany.
Freise
Chris E
CE
Serkova
Natalie
N
Niemann
Claus U
CU
Olson
Jean L
JL
Feng
Sandy
S
D000241:Adenosine; D000493:Allopurinol; D000818:Animals; D003404:Creatinine / Q000097:blood; D005978:Glutathione; D007166:Immunosuppressive Agents / Q000493:pharmacokinetics / Q000627:therapeutic use; D007328:Insulin; D007668:Kidney; D016030:Kidney Transplantation / Q000276:immunology* / Q000473:pathology / Q000502:physiology; D019188:Organ Preservation Solutions; D011887:Raffinose; D051381:Rats; D015427:Reperfusion Injury / Q000150:complications*; D020123:Sirolimus / Q000493:pharmacokinetics / Q000627:therapeutic use*; D013997:Time Factors; D014185:Transplantation, Isogeneic; D016896:Treatment Outcome
D007166:Immunosuppressive Agents; D007328:Insulin; D019188:Organ Preservation Solutions; C055206:University of Wisconsin-lactobionate solution; D000493:Allopurinol; D003404:Creatinine; D005978:Glutathione; D000241:Adenosine; D011887:Raffinose; D020123:Sirolimus