Liver microcirculation after selective denervation.

Microcirculatory disturbances have been related to a decrease in survival after liver transplant. Because innervation is involved in liver hemodynamics regulation, we decided to evaluate microcirculatory hepatic perfusion. Thirty rats were divided into three groups: denervated (DG), hepatic microsurgical denervation; manipulated (MG), hepatic manipulation; control (CG), laparotomy. Hepatic microcirculation was assessed in the median lobe using laser Doppler flowmetry in the following moments: T(0), after laparotomy and T(1), after denervation; and in the following moments after denervation: T(2), 10 minutes, T(3), 20 minutes, T(4), 30 minutes, T(5), 1 hour, T(6), 1.5 hours, and T(7), 2 hours for DG, and in same moments for MG and CG. DG showed a decrease in hepatic perfusion for 20 minutes after denervation, different from MG and CG. After that, there was recovery in hepatic perfusion in MG and DG (Kruskal-Wallis and Friedman tests). Therefore, denervation and manipulation alter hepatic microcirculation, but denervation promotes a more severe decrease than manipulation.

Gangliosides in rat femoral injury: early effect on intimal hyperplasia.

Previous studies demonstrated that some immunosuppressive agents inhibit arterial intimal hyperplasia. Our previous studies demonstrated that gangliosides (Gang) have an immunosuppressive effect on as well as an anti-inflammatory role in the wound-healing process. Therefore, we decided to examine the effect of Gang on intimal hyperplasia. Twenty Wistar isogenic rats received a transverse division of the anterior wall of the femoral artery, followed by suturing using mononylon 10-0 under surgical microscopy and were then divided into two groups: Gang group, 3 mg/kg per day of Gang, and control group, vehicle, intramuscularly from surgery to death (1 and 3 weeks, respectively). Concentric intimal hyperplasia was observed in arteries stained by hematoxylin-eosin in control and Gang groups. However, the media layer did not demonstrate any major alterations. After 3 weeks, the Gang group showed more intimal hyperplasia than the control group. Therefore, because intimal hyperplasia worsened in the presence of Gang after 3 weeks, further studies will be necessary to clarify its role in intimal proliferation.