Ischaemic preconditioning protects the rat kidney from reperfusion injury.
OBJECTIVE
To examine the possible role of ischaemic preconditioning (IPC), an adaptive pathophysiological phenomenon that increases tolerance to ischaemia-reperfusion (I-R) injury, in renal protection when rats are presented with an I-R challenge.


METHODS
Female Wistar rats (n=36) were divided randomly into four groups: (A) sham-operated controls; (B) IPC only; (C) renal ischaemia (RI) only; and (D) IPC+RI. The left kidney in groups B and D was preconditioned with four cycles of renal artery occlusion lasting 4 min, each occlusion separated by 11 min of reperfusion. The ischaemic insult, applied in groups C and D, comprised 40 min of sustained left renal artery occlusion. In Group D, the IPC cycle was completed 5 min before the start of the ischaemic insult. Differential left renal function was calculated by 99mTc-labelled dimercaptosuccinic acid scintigraphy at 0, 2 and 9 days after treatment, and expressed as a percentage of the total renal uptake.


RESULTS
The mean (sem) maximum decrease in left renal function, to 14.5 (4.3)% of the total, occurred on day 2 in Group C. The equivalent value in Group D showed relative preservation of function, at 36.0 (3.5)% (P=0.001 compared with Group C). The mean left renal function improved by day 9, to 39.6 (6.7)% (Group C) and 48.6 (1.5)% (Group D). The mean left renal function in Group B (50.5-53.9%) did not differ from that in controls (49.4-51.4%).


CONCLUSIONS
An IPC regimen applied 5 min before RI in the rat significantly protects it from the functional impairment associated with ischaemia and reperfusion.
Toosy
N
N
Division of Surgery, Anaesthetics and Intensive Care, Imperial College School of Medicine, Hammersmith Hospital, London, UK.
McMorris
E L
EL
Grace
P A
PA
Mathie
R T
RT
D000818:Animals; D005260:Female; D007511:Ischemia / Q000000981:diagnostic imaging / Q000503:physiopathology; D019194:Ischemic Preconditioning / Q000379:methods*; D007668:Kidney / Q000098:blood supply* / Q000502:physiology; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D051381:Rats; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000000981:diagnostic imaging / Q000517:prevention & control*; D019783:Technetium Tc 99m Dimercaptosuccinic Acid
D019275:Radiopharmaceuticals; D019783:Technetium Tc 99m Dimercaptosuccinic Acid