[The effect of L-arginine on the microcirculation reperfusion of cremaster muscle in rats].

OBJECTIVE: To investigate the effect of L-arginine and the role of nitric oxide (NO) on the microcirculation of cremaster muscle after the ischemia-reperfusion. METHODS: A group of male Sprague-Dawley rats, each weighing 180-220 g, were surgically prepared with the neurovascular bundle freed only to connect to the cremaster muscle, subjected to 5 hours warm ischemia and 2 hours of reperfusion, and treated with L-arginine. The microcirculation was observed with the measurement of the arteriole in diameter under intravital microscopy. RESULTS: 1. The arteriole re-flowing with the L-arginine treatment was significantly higher than the saline control with only 53% in 30 minutes after the reperfusion (P < 0.01). 2. The diameter of the reflowed arteriole and the perfused capillary density were increasing greatly with the L-arginine treatment, compared to the control group. 3. The pathological phenomena of "only irrigation and no reflow" was observed in local muscle microcirculation, which subsequently resulted in the large-scale leakage hemorrhage. CONCLUSIONS: The nitric oxide product could relieve the vasospasm and decrease the no-reflow of skeletal muscular during reperfusion; The venular no-reflow resulted from venular thrombi may play an important part during the tissue reperfusion injury.