Intermittent hilar occlusion attenuates or prevents renal ischaemia-reperfusion in mice.

Background: A minimal decrease in renal function in partial nephrectomy is an important clinical and experimental research objective. We compared the effect of intermittent hilar occlusion (IHO) and continuous hilar occlusion (CHO) on kidney injury and oxidative damage.

Method: Using CHO or IHO for 24, 30, and 45 min, intraoperative ischaemia, as well as a sham group, were set up in an ischaemia-reperfusion long-term survival mouse model. Renal function, pathological injury, subcellular structure injury, and cell apoptosis were evaluated at 1, 30, and 90 d postoperatively to study the protective effect of IHO. To do so, oxidative damage analysis, antioxidant activities, and ischaemia time dose-response curves on relative acute renal function injury were analysed.

Results: All parameters indicated that kidney injury was dramatically attenuated in the IHO groups compared to those in the corresponding CHO groups. Particularly, mice in the IHO 24-min group incurred no tubular injury or renal functional injury; mice in the CHO 30-min group incurred severe acute and chronic kidney injury, but mice in the IHO 30-min group only experienced transient mild renal functional injury. IHO prolonged tolerable ischaemia duration.

Conclusions: IHO can prolong the duration of tolerable ischaemia, at least partly through protecting the kidney from oxidative stress, consequently attenuating or preventing renal ischaemia-reperfusion injury. Reduced kidney injury after ischaemia-reperfusion is linked to a greater maintenance of antioxidant activity and less oxidative damage. The protective effect of IHO can be extremely efficient if properly applied; IHO may avoid renal ischaemia-reperfusion injury during partial nephrectomy.