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Objectives Ischemia–reperfusion (IR) features massive oxidative stress of tissues and cytokine response. Propofol and sevoflurane, both of which are commonly used anesthetics, are thought to have different antioxidant activities. The aim of this study is to delineate the influence of these two drugs on the production of free radicals and proinflammatory cytokines in IR conditions via in vitro and in vivo models. Methods An in vitro IR model was performed by incubating porcine cells (including mononuclear cells, and coronary and aortic smooth muscle cells) with either propofol 25 μM or sevoflurane 2% in the hypoxia chamber (1% O 2 , 37°C) for 1 hour, followed by room temperature air for 2 hours. Reactive oxygen species (ROS) and tumor necrosis factor-α (TNF-α) were also measured via flow cytometry and enzyme-linked immunosorbent assay methods, respectively. Ten pigs were used for the in vivo study. After anesthesia with either propofol (10–15 mg/kg/h) or sevoflurane (2%), internal carotid and femoral arterial catheters were inserted for direct blood pressure monitoring and blood sampling. The IR models were produced via descending thoracic aorta clamping for 1 hour and declamping for 2 hours during the procedure for left ventricular assist device implantation. Blood serum was sampled from upper and lower body vessels for ROS and TNF-α evaluation via thiobarbituric acid reacting substances method and enzyme-linked immunosorbent assay, respectively. Results The results showed significant reduction of both ROS and TNF-α levels in the propofol group in vitro IR model. However, there was no difference in lipid peroxidation and TNF-α level between propofol and sevoflurane for the in vivo IR model. Conclusion We concluded that propofol, compared with sevoflurane, can significantly inhibit ROS formation on a cell level. In addition, propofol can significantly inhibit TNF-α formation of monocytes and coronary smooth muscle cells but not aortic smooth muscle cells.

Objectives Both overproduction of nitric oxide and oxidative injury to the cardiovascular and pulmonary systems contribute to fatal pathophysiology during endotoxemia. We investigated the effect of propofol on oxidative stress-related enzymes in lung (L2), heart (H9C2) and macrophage (NR8383) cells during endotoxemia. Methods Experimental endotoxemia was induced by co-culture of Escherichia coli lipopolysaccharide (15 μg/mL) in the abovementioned three types of cells that were under the effect of propofol (15 or 30 μM for 1 or 4 hours). Cellular expression of induced nitric oxide synthase (iNOS), superoxide dismutase (SOD) 1 and 2, and p47phox (representing NADPH oxidase) were determined by immunoblotting. The cellular oxidative burst activity was determined using a dihydroethidium method via flow cytometry to represent the level of reactive oxygen species. The in vivo endotoxemia model was also employed for comparison using a systemic injection of lipopolysaccharide (15 mg/kg) under propofol maintenance (15 or 30 mg/kg/h). The Student t test (two groups) was used for statistical evaluation among the means, and the Newman–Keuls test was used for analysis of variance in the statistical analysis. Results In lung L2 cells, propofol significantly reduced the expression of iNOS, SOD1, SOD2, and p47phox under LPS-induced endotoxemia. However, in H9C2 cardiac cells and NR8383 macrophages, only the expression of iNOS was significantly suppressed, but not that of SOD1, SOD2, or p47phox. The level of reactive oxygen species was suppressed in all three kinds of cell. In in vivo animal tissue, except for the suppression of iNOS expression in lung and heart cells, propofol in lung cells produced only SOD1 suppression, but in rat heart the expression of both SOD1 and SOD2 was suppressed. Conclusion These results suggest that propofol may have a protective role for lung cells. This effect is associated with its suppression of oxidative-related enzymes, including iNOS, SOD1, SOD2, and p47phox. In cardiac myocytes and macrophages, propofol also provides an antioxidative effect, probably via its inhibition of iNOS. The overall effect of propofol in the organs may be a combination of its effects on various cells. In addition, a reduction in reactive oxygen species plays a major role in the beneficial effect of propofol on experimental endotoxemia.

Objectives Patients suffering from neuropathic pain are difficult to treat and many methods are used to resolve this issue. In this study, we used a model of neuropathic pain comprising rats with chronic constriction injury (CCI) on the left sciatic nerve to investigate the chronic effect of gabapentin via intrathecal administration. We also observed the expression of dorsal spinal protein kinase C gamma subunit (PKCγ) and other pain-related molecules in the spinal area which included cyclooxygenase 2 (COX2), c-Fos and cyclic AMP-dependent transcription factor (ATF3) in the neuropathic pain animals. Methods Male Sprague-Dawley (SD) rats (250–380g) were randomly assigned to four groups, i.e., control, gabapentin (Gaba), MK801, and gabapentin plus MK801 (Gaba+M) groups. A PE-5 catheter was inserted into the lumbar spine area via the cervical spine area. CCI was performed the following day after the intrathecal catheter implant surgery. Gabapentin (1.05μmol/day) was then given the following day after CCI surgery. Intrathecal gabapentin was administrated for 14 consecutive days. Pain-related behavior was assessed every 2 days thereafter by measuring the latency of foot withdrawal elicited by noxious radiant heat or Von Frey microfilament applied to the hind-paw plantar surface. MK801 (30μg/day), an N -methyl-D-aspartate (NMDA) receptor blocker, was also added for potential effect. The tissue of dorsal horn of the lumbar spine was harvested on the 14 th day for the expression of COX2, c-Fos, ATF3 and PKCγ with Western blotting, and positive finding protein was then checked on 7 th day for further evaluation. Results The beneficial effect of intrathecal gabapentin of statistic significance on thermal duration and mechanical microfilament appeared after 7-day and 11-day consecutive treatment, respectively. Furthermore, the NMDA receptor blocker also potentiated the effect on the behavior of thermal and mechanical stimulations. Gabapentin had no effect on the expression of COX2, c-Fos and ATF3. Interestingly, the expression of PKCγ in the spinal cord was initially inhibited by gabapentin on the 7 th day but was potentiated on the 14 th day. Conclusions Our results indicate that chronic intrathecal gabapentin has beneficial effects on the behaviors of both thermal and mechanical stimulations in the neuropathic pain animals and the NMDA blocker can potentiate this effect. Furthermore, gabapentin has biphasic effect on the expression of PKCγ in the spinal cord on Day 7 and Day 14 for the model rats with CCI.