Objective:To investigatethe transdermal delivery characteristics of methylphenidate hydrochloride (MPH) in vitro. Methods: Characteristics of MPH crossing nude rats skin were studied with Franz diffusion cells. A high performance liquid chromatographic (HPLC) method was established to determine the concentration of MPH crossed the skin. The permeability coefficient (P), steady state flux (J) and lag time(LT) for MPH through the skin of nude rats treated with various enhancers were compared with those of control. Results: The permeability coefficient increased with the increase of MPH concentration. The penetration of MPH through nude rats skin was obviously enhanced by 8%Azone and 5%propylene glycol (P

Objective To investigate the protective effect of a COX inhibitor,flurbiprofen (Flurb) on hepatic ischemia/reperfusion (IR) injury in rats and the action mechanism.Method C57BL/6 mice were randomized into sham,IR and Flurb (4 different doses) groups.The model of segmental (70％) warm hepatic ischemia was established in IR and Flurb groups.Flurbiprofen of different doses (5,7.5,10 and 15 mg/kg) was injected via the tail vein 20 min before ischemia.At different time points after reperfusion,liver cell necrosis and apoptosis were evaluated by HE and TUNEL staining.The COX and inflammatory cytokine gene expression was detected by using realtime PCR.Liver mitochondria were separated and mitochondrial permeability transition (MPT) pore sensitivity was examined by using swelling assay and fluorescence spectrophotometry assay.Result In flurbiprofen groups of different doses,the serum AST and ALT levels were significantly decreased at 6 h after reperfusion as compared with IR group.Moreover,10 mg/kg Flurb pretreatment significantly inhibited the mitochondrial permeability transition (MPT) pore opening,and thus alleviated liver cell damage and prevented mitochondria-related cell death and apoptosis by inhibiting COX-2 and inflammatory factor genes expression such as IL-1β,IL-6 and TNF-α.Conclusion Flurbiprofen protects mice from hepatic I/R injury possibly by inhibiting mitochondrial permeability transition and IL-1β,IL-6 and TNF-α expression,which may provide experimental evidence for clinical use of flurbiprofen to protect liver function in surgical settings other than its conventional use for pain relief.

Diabetic neuropathic pain (DNP) is the most common disabling complication of diabetes. Emerging evidence has linked the pathogenesis of DNP to the aberrant sprouting of sensory axons into the epidermal area; however, the underlying molecular events remain poorly understood. Here we found that an axon guidance molecule, Netrin-3 (Ntn-3), was expressed in the sensory neurons of mouse dorsal root ganglia (DRGs), and downregulation of Ntn-3 expression was highly correlated with the severity of DNP in a diabetic mouse model. Genetic ablation of Ntn-3 increased the intra-epidermal sprouting of sensory axons and worsened the DNP in diabetic mice. In contrast, the elevation of Ntn-3 levels in DRGs significantly inhibited the intra-epidermal axon sprouting and alleviated DNP in diabetic mice. In conclusion, our studies identified Ntn-3 as an important regulator of DNP pathogenesis by gating the aberrant sprouting of sensory axons, indicating that Ntn-3 is a potential druggable target for DNP treatment.
Mice ; Animals ; Diabetes Mellitus, Experimental/metabolism* ; Axons/physiology* ; Diabetic Neuropathies ; Sensory Receptor Cells/metabolism* ; Neuralgia/metabolism*