Buflomedil hydrochloride attenuates tourniquet-induced microvascular reperfusion injury in striated muscle.

With the use of intravital fluorescence microscopy and the dorsal skinfold chamber model we studied the effect of buflomedil hydrochloride on microvascular reperfusion injury after 4 h of tourniquet-induced ischemia in hamster striated muscle. Animals (n = 15) received 3 mg/kg buflomedil (i.v. bolus) 5 min before onset of reperfusion, and 3 mg/kg buflomedil (continuous i.v. infusion) during the first 20 min of reperfusion. Animals (n = 13) receiving equivalent volumes of saline served as controls. Tourniquet-induced ischemia resulted in (a) a marked decrease of functional capillary density and (b) accumulation and adherence of leukocytes in postcapillary venules after 30 min and 2 h of reperfusion. This was associated with an increased microvascular permeability (leakage of macromolecules), reflecting the alteration of endothelial cell integrity. Treatment with buflomedil significantly reduced both post-ischemic capillary perfusion failure and leukocyte adherence in venules. Concomitantly, the increase of microvascular permeability in postcapillary venules was almost prevented, indicating the beneficial effect of buflomedil on the manifestation of microvascular reperfusion injury following tourniquet ischemia in striated muscle.