Objective To investigate the analgesic effect of a specific p38MAPK inhibitor SB203580 in a rat model of chronic constriction injury (CCI) to sciatic nerve. Methods Male SD rats weighing 220-250 g were used in this study. The neuropathic pain model was established by CCI to sciatic nerve. The rats were anesthetized with intraperitoneal (i.p.) pentobarbital 40 mg?kg-1. Left sciatic nerve was exposed and 4 loose ligatures were placed on left sciatic nerve at 1 mm intervals with 4-0 silk suture. The animals were allowed 7 days to recover from surgery. Intrathecal (IT) SB203S80 was given through a needle inserted at L5,6 interspace. In experiment A, 40 rats wee randomly divided into 5 groups (n = 8 each): control group and 4 SBgroups (SB203580 0.1, 0.5, 2.5 and 5.0 ?g were given respectively) . Response of the hindpaw to mechanical stimulation with von Frey filament (MWT) was measured before (T0,baseline) and at 0.5, 3, 6, 12 and 24 h (T1-5) after IT SB203580 injection. In experiment B, 36 animals were randomly divided into 6 groups (n = 6 each): (1) sham operation group; (2) CCI group; (3) DMSO group; (4) SB 0.1 ?g group; (5) SB 0.5 ?g group and (6) SB 5.0 ?g group. The animals were lulled at 6h after IT SB203580 administration and L5,6 lumbar segment of the spinal cord was removed for determination of pCREB expression in the dorsal horn by immuno-cytochemistry. Results The rats developed hyperalgesia after CCI and IT SB203580 administration significantly increased MWT in a dose dependent manner. The number of pCREB positive neurons in the L4,5 spinal dorsal horn was significantly increased after CCI. Interthecal administration of SB203580 0.5 or 5.0 ?g significantly inhibited the CCI-induced increase in pCREB expression. Conclusion Intrathecal administration of SB203580 can attenuate the hyperalgesia induced by CCI and inhibition of CREB phosphorylation in the spinal dorsal horn is involved in the mechanism.

Objective To investigate the protective effect of meglumine adenosine cyclosphosp (MAC) on the cerebral ischemia-reperfusion (I/R) injury in rabbits.Methods Twenty four healthy rabbits were randomly divided into control group (n =6),I/R group (n =6),MAC pretreated group (n =6),and MAC treated group (n =6).Cerebral ischemia-reperfusion injury model was made by separating and electrocoagulating vertebral arteries and clipping common carotid arteries in the latter 3 groups after anesthesia.The sham-operated group underwent vessel separation without clipping.L/R group was administered with nothing,while MAC pretreated group with MAC before ischemia,and MAC treated group with MAC just after ischemia.Blood was gathered from jugular vein before ischemia,and 30 min,1 h,and 2 h after reperfusion for testing IL-8,superoxide dismutase (SOD) and malondialdehyde (MDA).The brain tissue slice was observed by optical microscope.Results Compared to control group and before ischemia,the levels of IL-8 and SOD in serum were significantly increased and decreased,and the levels of MDA was significantly increased at 30 min after reperfusion in I/R group; the levels of IL-8 and MDA in serum were significantly increased,and the levels of SOD in serum was significantly decreased at 1 h and 2 h after reperfusion in I/R group.The levels of IL-8 in serum was less at 30 min and 1 h and 2 h after reperfusion in MAC pretreated group than in I/R group.At 1 h and 2 h after reperfusion,the levels of MDA in serum was less and the levels of SOD in serum was higher in MAC pretreated group than in I/R group.At 1 h and 2 h after reperfusion,the levels of IL-8 in serum were less and the levels of SOD in serum were higher in MAC treated group than in I/R group.The levels of MDA in serum were less at 2 h after reperfusion in MAC treated group than in I/R group.Compared to I/R group,pathological change was lighter in the MAC pretreated and MAC treated group.Conclusions MAC has a fine cerebral-protective effect and has no side effect.

Objective To analyze the pharmacodynamic interaction of esketamine and propofol in hysteroscopic surgery by response surface method.Methods Forty-five patients underwent elective hystero-scopic surgery,aged 18.5-64.0 years,BMI 18.5-28.0 kg/m2,ASA physical status Ⅰ or Ⅱ.Compound propofol target control infusion of esketamine(0,0.1,0.2,0.3,0.4,0.5,0.6,0.7,and 0.8 μg/ml)with different plasma drug concentrations were selected to keep the plasma drug concentration of esketamine unchanged,and the plasma drug concentration of propofol was increased step by step.To evaluate body re-sponse caused by dilation of the cervix.A response surface model was used to analyze the pharmacodynamic interaction of esketamine and propofol.Results The three-dimensional response surface of esketamine(0.0-0.8 μg/ml)and propofol(1.0-7.0 μg/ml)showed that the two have an additive effect in sedation and inhibition of body activity reaction caused by dilated cervix.The median effective concentration(EC50)of esketamine was 0.61 μg/ml(95％CI 0.41-0.81 μg/ml),and the EC50 of propofol was 4.69 μg/ml(95％CI 3.17-6.21 μg/ml)when inhibits the body activity reaction caused by dilated cervix.Conclusion Response surface method can qualitatively and quantitatively analyze the pharmacodynamic interaction of es-ketamine and propofol.Esketamine and propofol have additive effects in inhibiting the body activity reaction caused by dilated cervix.