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Objective@#To evaluate the effect of dexmedetomidine on hypoxia-inducible factor-1alpha (HIF-1 α) signaling pathway during hypoxia in mice with lung cancer.@*Methods@#Eighteen clean-grade healthy adult male BALB/c nude mice, aged 8 weeks, weighing 20-30 g, were divided into 3 groups (n=6 each) using a random number table method: lung cancer group (group L), hypoxia+ lung cancer group (group HL), and hypoxia plus lung cancer plus dexmedetomidine group (group HLD). Human lung adenocarcinoma A549 cell suspension 1×106/150 μl was injected via the tail vein to establish the mouse model of lung cancer.After the model was established successfully, chronic intermittent hypoxia was performed as follows: the mice were placed in air-tight modular incubation chambers, and the atmosphere was controlled by a constant gas flow containing 10% O2 for 3 h once a day for 3 weeks.The mice in group HL were exposed to hypoxia.After the end of hypoxia exposure, the animals in group HLD were intraperitoneally injected with dexmedetomidine 25 μg/kg 3 times a week for 3 weeks in total.The mice in group L were placed in air-tight modular incubation chambers and the atmosphere was controlled by a constant gas flow containing 21% O2 for 3 h once a day for 3 weeks, and the equal volume of normal saline was injected intraperitoneally.The mice were sacrificed by cervical dislocation, and the lung tissues were removed for determination of lung cancer nodules count, HIF-1α expression (by immunohistochemistry), expression of HIF-1α, survivin and X chromosome linked inhibitor of apoptosis protein (XIAP) (by Western blot), and expression of matrix metalloproteinase-2 (MMP-2) and MMP-9 (by real-time polymerase chain reaction).@*Results@#Compared with group L, the number of lung cancer nodules was significantly increased, and the expression of HIF-1α, survivin, XIAP, MMP-2 and MMP-9 was up-regulated in the other two groups (P<0.05). Compared with group HL, the number of lung cancer nodules was significantly increased, and the expression of HIF-1α, survivin, XIAP, MMP-2 and MMP-9 was up-regulated in group HLD (P<0.05). A small number of HIF-1α positive cells were found in group L, a medium number of HIF-1α positive cells in group HL, and a large number of HIF-1α positive cells in group HAD.@*Conclusion@#Dexmedetomidine can promote proliferation of tumor cells in mice with lung cancer during hypoxia, and the mechanism is related to activating HIF-1α signaling pathway.
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Objective@#To evaluate the effect of dexmedetomidine on renal fibrosis in a mouse model of renal ischemia-reperfusion (I/R) and the role of serine-threonine kinase (Akt).@*Methods@#Sixty male C57BL/6 mice, aged 8 weeks, weighing 20-25 g, were divided into 5 groups (n=12 each) using a random number table method: sham operation group (S group), renal I/R group (I/R group), renal I/R plus dexmedetomidine group (I/R + D group), renal I/R plus dexmedetomidine plus Akt agonist SC79 group (I/R + D + SC group), and renal I/R plus dexmedetomidine plus normal saline group (I/R+ D+ NS group). Renal I/R injury model was established by clamping the bilateral renal pedicle for 30 min followed by reperfusion.Dexmedetomidine was intraperitoneally injected at 30 min before surgery in I/R+ D, I/R+ D+ SC and I/R+ D+ NS groups.SC79 was intraperitoneally injected as a bolus of 0.04 mg/kg at 1 min of reperfusion, followed by an intraperitoneal injection of the same dose every 24 h until day 7.The serum blood urea nitrogen (BUN) and Scr concentrations were detected at 24 h of reperfusion.Renal tissues were taken, and the damage to the renal tubules was scored.Renal tissues were removed at 14 days of reperfusion to detect the degree of renal fibrosis and expression of collagen 1 (COL1), fibronectin (FN), and α-smooth actin (α-SMA) (by immunofluorescence and Western blot). The expression of phosphorylated Akt (p-Akt) in renal tissues was determined by Western blot at 24 h and 14 day of reperfusion.@*Results@#Compared with group S, the serum BUN and Scr concentrations, renal tubule damage score and degree of renal fibrosis were significantly increased, and the expression of COL1, FN, α-SMA and p-Akt was up-regulated in group I/R (P<0.05). Compared with I/R group, the serum BUN and Scr concentrations, renal tubular damage score and degree of renal fibrosis were significantly decreased, and the expression of COL1, FN, α-SMA and p-Akt was down-regulated in I/R+ D and I/R+ D+ NS groups (P<0.05). Compared with I/R+ D group, the serum BUN and Scr concentrations, renal tubule damage score and degree of renal fibrosis were significantly increased , and the expression of COL1, FN, α-SMA and p-Akt was up-regulated in I/R+ D+ SC group (P<0.05).@*Conclusion@#Dexmedetomidine can reduce the degree of renal fibrosis in a mouse model of renal I/R and the mechanism is related to inhibiting activation of Akt.
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Objective To evaluate the effect of pulsed radiofrequency (PRF) on the phenotypic transformation of the lumbar sympathetic ganglion (LSG) in the rats with diabetic neuropathic pain (PDN).Methods Twenty-four clean-grade healthy adult male Sprague-Dawley rats,aged 2 months,weighing 180-220 g,were divided into 4 groups (n =6 each) according to the method of random number table:control group (group C),group PDN,group PRF,and PRF control group (group PC).The PDN model was established by intraperitoneal injection of streptozotocin 60 mg/kg in anesthetized rats.Citrate-sodium citrate buffer 6 ml/kg was intraperitoneally injected in group C.Group PC only received radiofrequency needle puncture.PRF was performed on the right L3 LSG in group PRF.The mechanical paw withdrawal threshold (MWT) to yon Frey filament stimulation was measured before intraperitoneal injection (baseline,T0),before PRF and at 1,3,5,7 and 14 days after PRF.The rats were then sacrificed,and ipsilateral L3 LSGs were removed for determination of the expression of tyrosine hydroxylase (TH) and vesicle glutamate transporter2 (VGLUT2) in LSGs (by double immunofluorescent staining) and for examination of pathological changes (with a light microscope).The number of neurons expressing VGLUT2 was counted.Results Compared with group C,the MWT was significantly decreased at T1-6,and the number of neurons expressing VGLUT2 was increased at T6 in PDN,PC and PRF groups (P＜0.05).Compared with PDN and PC groups,the MWT was significantly increased at T2-6,and the number of neurons expressing VGLUT2 was decreased at T6 in group PRF (P＜0.05).TH expression in LSGs was found,and no VGLUT2 expression in LSGs was observed in group C,the expression of TH and VGLUT2 in LSGs was found in the other three groups,especially in PDN and PC groups,and most of the neurons expressing VGLUT2 expressed TH simultaneously.Conclusion The mechanism by which PRF mitigates PDN is related to inhibiting the phenotypic transformation of LSGs in the rats.
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Objective To evaluate the effect of dexmedetomidine on hypoxia-inducible factor1alpha (HIF-1 α) signaling pathway during hypoxia in mice with lung cancer.Methods Eighteen cleangrade healthy adult male BALB/c nude mice,aged 8 weeks,weighing 20-30 g,were divided into 3 groups (n=6 each).using a random number table method:lung cancer group (group L),hypoxia+lung cancer group (group HL),and hypoxia plus lung cancer plus dexmedetomidine group (group HLD).Human lung adenocarcinoma A549 cell suspension 1× 106/150 μl was injected via the tail vein to establish the mouse model of lung cancer.After the model was established successfully,chronic intermittent hypoxia was performed as follows:the mice were placed in air-tight modular incubation chambers,and the atmosphere was controlled by a constant gas flow containing 10％ O2 for 3 h once a day for 3 weeks.The mice in group HL were exposed to hypoxia.After the end of hypoxia exposure,the animals in group HLD were intraperitoneally injected with dexmedetomidine 25 μg/kg 3 times a week for 3 weeks in total.The mice in group L were placed in air-tight modular incubation chambers and the atmosphere was controlled by a constant gas flow containing 21％ O2 for 3 h once a day for 3 weeks,and the equal volume of normal saline was injected intraperitoneally.The mice were sacrificed by cervical dislocation,and the lung tissues were removed for determination of lung cancer nodules count,HIF-1α expression (by immunohistochemistry),expression of HIF-1α,survivin and X chromosome linked inhibitor of apoptosis protein (XIAP) (by Western blot),and expression of matrix metalloproteinase-2 (MMP-2) and MMP-9 (by real-time polymerase chain reaction).Results Compared with group L,the number of lung cancer nodules was significantly increased,and the expression of HIF-1α,survivin,XIAP,MMP-2 and MMP-9 was up-regulated in the other two groups (P＜0.05).Compared with group HL,the number of lung cancer nodules was significantly increased,and the expression of HIF-1α,survivin,XIAP,MMP-2 and MMP-9 was up-regulated in group HLD (P＜0.05).A small number of HIF-1α positive cells were found in group L,a medium number of HIF-1α positive cells in group HL,and a large number of HIF-1α positive cells in group HAD.Conclusion Dexmedetomidine can promote proliferation of tumor cells in mice with lung cancer during hypoxia,and the mechanism is related to activating HIF-1α signaling pathway.
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Objective To evaluate the effect of dexmedetomidine on renal fibrosis in a mouse model of renal ischemia-reperfusion (I/R) and the role of serine-threonine kinase (Akt).Methods Sixty male C57BL/6 mice,aged 8 weeks,weighing 20-25 g,were divided into 5 groups (n=12 each) using a random number table method:sham operation group (S group),renal I/R group (I/R group),renal I/R plus dexmedetomidine group (I/R + D group),renal I/R plus dexmedetomidine plus Akt agonist SC79 group (I/R + D + SC group),and renal I/R plus dexmedetomidine plus normal saline group (I/R+D+NS group).Renal I/R injury model was established by clamping the bilateral renal pedicle for 30 min followed by reperfusion.Dexmedetomidine was intraperitoneally injected at 30 rmin before surgery in I/R+D,I/R+D+SC and I/R+D+NS groups.SC79 was intraperitoneally injected as a bolus of 0.04 mg/kg at 1 min of reperfusion,followed by an intraperitoneal injection of the same dose every 24 h until day 7.The serum blood urea nitrogen (BUN) and Scr concentrations were detected at 24 h of reperfusion.Renal tissues were taken,and the damage to the renal tubules was scored.Renal tissues were removed at 14 days of reperfusion to detect the degree of renal fibrosis and expression of collagen 1 (COL1),fibronectin (FN),and α-smooth actin (α-SMA) (by immunofluorescence and Western blot).The expression of phosphorylated Akt (p-Akt) in renal tissues was determined by Western blot at 24 h and 14 day of reperfusion.Results Compared with group S,the serum BUN and Scr concentrations,renal tubule damage score and degree of renal fibrosis were significantly increased,and the expression of COL1,FN,α-SMA and p-Akt was up-regulated in group I/R (P＜0.05).Compared with I/R group,the serum BUN and Scr concentrations,renal tubular damage score and degree of renal fibrosis were significantly decreased,and the expression of COL1,FN,α-SMA and pAkt was down-regulated in I/R+D and I/R+D+NS groups (P＜0.05).Compared with I/R+D group,the serum BUN and Scr concentrations,renal tubule damage score and degree of renal fibrosis were significantly increased,and the expression of COL1,FN,α-SMA and p-Akt was up-regulated in I/R+D+SC group (P＜0.05).Conclusion Dexmedetomidine can reduce the degree of renal fibrosis in a mouse model of renal I/R and the mechanism is related to inhibiting activation of Akt.
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Objective To observe the effect of intrathecal injection of TRESK overexpression adenoviruson phosphorylation of JNK and apoptosis of neurons in neuropathic pain rats.Methods Seventy-two male SD rats were randomly divided into six groups:groups C,S,NP,T,V,and NS,12 for each group.SNI was administrated to rats in groups NP,T,V and NS.TRESK adenovirus and negative virus were intrathecally injected after use of SNI in groups T and V,while equal volume of NS was injected to rats in group NS.MWT and TWL were measured at 1 day before operation(baseline,BL)and at 1,3,7 and 14 days after operation (days 1,3,7,and 14).Six rats in each group were sacrificed at D7 to determinate the expression of TRESK protein of DRG.The other rats were sacrificed at D14 to determinate neural apoptosis and the expressions of caspase3 and p-JNK of DRG.Results As compared with groups C,S and T,the expression of TRESK protein was significantly decreased at D7 in groups NP,NS and V (P＜0.05).Compared with groups C and S,MWT was significantly decreased at days 1,3,7 and 14 (P＜0.05),phosphorylation of JNK in DRG was significantly increased at D14 (P＜0.05),neuronal apoptosis rate and expressions of Caspase3 of DRG were significantly increased at D14 (P＜0.05) in groups NP,T,NS and V.Compared with groups NP,V and NS,MWT was significantly increased at time points of days 1,3,7 and 14 in group T (P＜0.05),phosphorylation of JNK of in DRG was significantly decreased at D14 in group T (P＜0.05),neuronal apoptosis rate and expression of Caspase3 of DRG were significantly decreased at D14 in group T (P＜0.05).Intrathecal injection ofpAd/CMV/VS-DEST-TRESK obviously reduced mechanical hyperalgesia,upregulated TRESK expression,and lowered JNK phosphorylation and NP in SNI rat.Conclusions Intrathecal injection of TRESK over expression adenovirus relieves NP via inhibiting JNK activation and neuronal apoptosis.
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Objective To evaluate the changes in the expression of adaptor protein containing pleck-strin homobgy domain, phosphotyrosine-binding domain and a leucine zipper motif 1(APPL1)during renal fibrosis in a mouse model of renal ischemia-reperfusion(I∕R)injury. Methods Twenty-four male C57BL∕6 mice, aged 8 weeks, weighing 20-25 g, were divided into 2 groups(n=12 each)using a random number table: sham operation group(S group)and renal I∕R group.The model of renal I∕R injury was established by clipping the bilateral renal pedicles for 30 min followed by reperfusion in group I∕R.Six mice were selected at 2 days of reperfusion, and venous blood samples were collected for determination of serum concentrations of blood urea nitrogen and creatinine.The animals were then sacrificed, the renal specimens were obtained for microscopic examination of tubular necrosis with a light microscope, and the damage to the renal tubules was scored using a semi-quantitative method.Six mice were sacrificed at 14 days of reperfusion, and the renal specimens were obtained for assessment of the degree of renal fibrosis(using picric acid-sirius red staining) and for determination of the expression of collagen type 1, fibronectin and α-smooth muscle actin in renal tis-sues(by Western blot or immunofluorescence method). At 2 and 14 days of reperfusion, the expression of APPL1 in renal tissues was detected by Western blot and the expression of APPL1 mRNA in renal tissues by real-time polymerase chain reaction. Results Compared with group S, the serum concentrations of blood u-rea nitrogen and creatinine, scores of renal tubular damage and degree of renal fibrosis were significantly in-creased at 2 days of reperfusion, the expression of collagen type 1, fibronectin and α-smooth muscle actin in renal tissues was up-regulated at 14 days of reperfusion, and the expression of APPL1 protein and mRNA was up-regulated at 2 and 14 days of reperfusion in group I∕R(P<0.05). Conclusion Up-regulated expression of APPL1 may be involved in the process of renal fibrosis in a mouse model of renal I∕R injury.
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Objective To evaluate the role of interleukin-4 receptor (IL-4R) in renal fibrosis following renal ischemia-reperfusion (I/R) injury in mice.Methods Twelve male wild type BALB/C mice and 12 IL-4Rα gene-knockout mice,aged 8-10 weeks,weighing 20-30 g,were used in the study.The mice of either type were divided into 2 groups (n =6 each) using a random number table:sham operation group (group S) and group I/R.In group I/R,renal I/R was induced by occlusion of the right renal artery for 1 h with atraumatic microclips followed by 2 weeks of reperfusion.The right renal artery was only isolated in group S.At 2 weeks of reperfusion,blood samples were taken from the orbital vein for determination of the concentrations of serum blood urea nitrogen (BUN) and creatinine (Cr).The renal tissues were obtained,and the renal fibrosis area was measured by Sirius Red staining.The expression of fibronectin (FN),collagen Ⅰ (COL-Ⅰ) and α-smooth muscle actin (α-SMA) in renal tissues was detected by immunofluorescence.The expression of signal transducer and activator of transcription 6 (STAT6) and phospho-STAT6 in renal tissues was determined by Western blot.The ratio of phoshop-STAT6 to STAT6 was calculated to reflect the phosphorylation of STAT6.Results Compared with group S of wild type mice,the serum BUN and Cr concentrations and renal fibrosis area were significantly increased,the expression of FN,COL-Ⅰ and α-SMA in renal tissues was significantly up-regulated,and the phosphorylation of STAT6 in renal tissues was significantly increased in group I/R of wild type and IL-4Rα KO mice (P＜0.05).Compared with group I/R of wild type mice,the serum BUN and Cr concentrations and renal fibrosis area were significantly decreased,the expression of FN,COL-Ⅰ and α-SMA in renal tissues was significantly down-regulated,and the phosphorylation of STAT6 in renal tissues was significantly decreased in group I/R of IL-4RαKO mice (P＜0.05).Conclusion The mechanism of renal fibrosis following renal I/R injury is partially related to IL-4R,and IL-4R results in renal fibrosis through promoting activation of STAT6 signaling pathway in mice.
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Objective To observe the effect of adenosine monophosphate activated protein kinase (AMPK) on attenuating inflammation in fibrosis induced hy acute ischemia reperfusion injury (IRI) in mice.Methods Forty eight male C57BL/6 mice were randomly divided into four groups:sham operation group (sham group),IRI group,AMPK inhibitor+IRI group (AMPK/IRI group) and normal saline+IRI group (NS/IRI group),12 mice each group.The mice with renal IRI were occluded for 30 min through clipping bilateral renal pedicle,then released renal perfusion.Mice in sham group were performed the separation of renal pedicle without clipping.Mice in AMPK/IRI group and NS/IRI group were respectively intraperitoneal injected AMPK inhibitor and normal saline before IRI.At the 2 d after operation,6 randomly-selected mice from each group were blooded by extraction eyeball to detect BUN and Scr.The renal histopathological changes were observed through HE staining.The mRNA expression of IL-1β,IL-6 and TNF-α was detected by real time PCR,and the level of AMPK phosphorylation was detected by Western blotting.At the 14 d after operation,Collagen 1 (COL1),α-SMA and fibronectin (FN) were detected by immunofluorescence and Western blotting in 6 remained mice from each group.The degree of kidney fibrosis was observed through sirus red staining.Results Compared with those in sham group,tubular interstitial damage was aggravated (P ＜ 0.05),BUN and Scr were increased (P ＜ 0.05),the mRNA expression of IL-1β,IL-6 and TNF-α was increased at the 2 d after operation (all P ＜ 0.05),and the level of AMPK phosphorylation was activated in IRI group and NS/IRI group (all P ＜ 0.05);the degree of kidney fibrosis and the expression of COL1,α-SMA and FN were increased obviously at the 14 d (all P ＜ 0.05).Compared with those in IRI group,in AMPK/IRI group tubular interstitial damage was aggravated (P ＜ 0.05),BUN and Scr were increased (all P ＜ 0.05),the mRNA expression of IL-1β,IL-6 and TNF-α was increased at the 2 d (all P ＜ 0.05),and the level of AMPK phosphorylation was decreased (P ＜ 0.05).Moreover,the degree of kidney fibrosis and the expression of COLI,α-SMA and FN were increased obviously at the 14 d in AMPK/IRI group (all P ＜0.05).Conclusions AMPK can ameliorate the acute renal ischemia reperfusion injury induce fibrosis in mice,and the mechanism may be related to the decrease of inflammatory reaction.
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Objective To evaluate the role of T?type calcium channels in up?regulation of spinal Ca2+∕calmodulin?dependent protein kinase Ⅱ ( CaMKⅡ) expression in rats with neuropathic pain. Meth?ods Forty?eight male Sprague?Dawley rats, weighing 230-270 g, in which intrathecal catheters were suc?cessfully implanted, were divided into 4 groups ( n=12 each) using a random number table: sham opera?tion group (group S), neuropathic pain group (group NP), normal saline group (group NS), and T?type calcium channel blocker mibefradil group ( group M ) . The model of neuropathic pain was established by chronic compression of the dorsal root ganglion ( DRG) . Normal saline 20μl and mibefradil 200μg ( dilu?ted to 20μl in normal saline) were injected intrathecally at 5 days after compression of the DRG in NS and M groups, respectively. Before intrathecal catheter implantation ( T1 ) , before compression of the DRG ( T2 ) , at 5 days after compression of the DRG and before intrathecal administration ( T3 ) , and at 30, 60, 120 and 240 min after intrathecal administration ( T4?7 ) , the mechanical paw withdrawal threshold ( MWT) and thermal paw withdrawal latency ( TWL) were measured. The rats were sacrificed after the last measure?ment of the pain threshold at T7 , and the lumbar enlargement segments of the spinal cord were harvested for determination of CaMKⅡ expression by Western blot. Results Compared with group S, the MWT was significantly decreased, and TWL was significantly shortened at T3?7 , and the expression of spinal CaMKⅡ was significantly up?regulated in NP and M groups (P0.05). Conclusion T?type calcium channels are opened, the intra?cellular free calcium ion concentrations are increased, and activated spinal CaMKⅡ is involved in the de?velopment of neuropathic pain in rats.
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<p><b>OBJECTIVE</b>To investigate the effect of KN93, a calmodulin-dependent protein kinase II (CaMK II) inhibitor, on SH-SY5Y cell injury induced by bupivacaine hydrochloride.</p><p><b>METHODS</b>SH-SY5Y cells exposed for 24 h to 1 mmol/L KN93, 1 mmol/L bupivacaine hydrochloride, or both were examined for morphological changes and Cav3.1 protein expressions using Western blotting. The vitality and apoptosis rate of the cells at different time points during the exposures were assessed with MTT assay and flow cytometry, respectively.</p><p><b>RESULTS</b>Bupivacaine hydrochloride exposure caused obvious cell morphologial changes, reduced cell viability, increased cell apoptosis, and enhanced Cav3.1 protein expression. All these changes were partly reversed by treatment of the cells with 1 mmol/L KN93.</p><p><b>CONCLUSIONS</b>CaMKII may play a role in bupivacaine hydrochloride-induced SH-SY5Y cells injury, which is related with upregulated Cav3.1 protein expression.</p>
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Humans , Apoptosis , Bupivacaine , Calcium Channels, T-Type , Metabolism , Calcium-Calmodulin-Dependent Protein Kinase Type 2 , Metabolism , Cell Line , Cell Survival , Up-RegulationABSTRACT
Objective To evaluate the effects of intrathecal TRESK gene recombinant adenovirus on inflammatory responses mediated by chemokine in the spinal cord of rats with neuropathic pain ( NP ) . Methods Thirty?six male Sprague?Dawley rats, weighing 200-250 g, were randomly divided into 6 groups (n=6 each) using a random number table: control group (group C); sham operation group (group S);NP group; TRESK?overexpressed adenovirus group ( group TRESK ); negative adenovirus group ( group Virus); normal saline group ( group NS) . Spinal nerve injury was produced by exposing the sciatic nerve and its branches and ligation and transection of tibial nerve and common fibular nerve in anesthetized rats. In TRESK, Virus and NS groups, pAd∕CMV∕V5?DEST?TRESK 25 μl (109IU∕ml), negative adenovirus 25 μl and normal saline 25 μl were intrathecally injected, respectively. At 1 day before operation ( base?line, T0 ) and 1, 3, 7 and 14 days after operation ( T1-4 ) , the mechanical paw withdrawal threshold ( MWT) and thermal paw withdrawal latency were measured. Six rats in each group were sacrificed after measurement of pain threshold at T3 . The L4,5 segments of the spinal cords were removed for determination of monocyte chemotactic protein?1 ( MCP?1) , MIP?2, tumor necrosis factor?alpha ( TNF?α) , interleukin?1 beta ( IL?1β) and IL?6 mRNA expression by real?time PCR. Results There was no significant difference in thermal paw withdrawal latency at each time point between groups. Compared with C and S groups, MWT at T1-4 in NP and TRESK groups and at T1-3 in Virus and NS groups were significantly decreased, and the expression of MCP?1, MIP?2, TNF?α, IL?1βand IL?6 mRNA was up?regulated in NP, TRESK, Virus and NS groups. Compared with group NP, MWT was significantly increased at T1-4, and the expres?sion of MCP?1, MIP?2, TNF?α, IL?1β and IL?6 mRNA was down?regulated in group TRESK. Conclusion The mechanism by which intrathecal TRESK gene recombinant adenovirus reduces NP is re?lated to inhibition of inflammatory responses mediated by chemokine in the spinal cord of rats.
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Objective To evaluate the effects of dexmedetomidine on the cellular immune function of the rats with scald.Methods Seventy-two healthy male Sprague-Dawley rats,weighing 200-220 g,aged 120-150 days,were randomly divided into 3 groups (n =24 each):normal control group (group C),scald group (group S) and dexmedetomidine group (group D).Thirty percent of the total body surface was shaved and then exposed to 94 ℃ water for 12 s in S and D groups.The rats were resuscitated according to Parkland formula after scald in S and D groups,and in addition,dexmedetomidine 30 μg/kg was also intraperitoneally injected immediately after scald in D group.Before the model was established (T1) and at 12 and 24 h after scald (T2,3),blood samples from the inferior vena cava were collected for determination of T lymphocyte subsets CD3 +,CD4 + and CD8 +,NK cell,C-reactive protein (CRP),interleukin-6 (IL-6),IL-10 and tumor necrosis factor-alpha (TNF-α) level.CD4+/CD8+ was calculated.Arterial blood samples were collected for blood gas analysis.Results Compared with C,the CD3+,CD4+ and NK cell levels,CD4+/CD8+,pH value,PaCO2 and PaO2 were significantly decreased,and CD8+ levels,IL-6,IL-10,TNF-α,CRP and BE negative value were increased at T2,3 in S and D groups.Compared with group S,the CD3+,CD4+,NK cell and IL-10 levels,CD4+/CD8+,pH value,PaCO2 and PaO2 were significantly increased,and CD8+ levels,IL-6,TNF-α,CRP and BE negative value were decreased at T2,3 in group D.Conclusion Dexmedetomidine can improve the cellular immune function of the rats with scald.
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Objective To evaluate the role of calcium/calmodulin-dependent protein kinase Ⅱ (CaMK Ⅱ) in the up-regulation of expression of Cav3.2 T-type calcium channels in spinal cord in a rat model of neuropathic pain (NP).Methods Forty-eight male Sprague-Dawley rats,aged 3 months,weighing 220-250 g,were randomly divided into 6 groups (n =8 each)∶ sham operation group (group S),group NP,dimethyl sulfoxide group (group D) and different concentrations of a specific CaMK Ⅱ inhibitor KN93 groups (groups K1-3).NP was produced by chronic compression of dorsal root ganglion.The rats in groups D and K1-3 received a single intrathecal injection of dimethyl sulfoxide and KN93 15,30,60 nmol/L (10 μl),respectively,on 5th day after NP.Paw withdrawal threshold to von Frey filament stimulation (MWT) and paw withdrawal latency to thermal nociceptive stimulus (TWL) were measured before NP,before intrathecal injection on 5th day after NP,and at 30 and 60 min and 3,6 and 8 h after intrathecal injection on 5th day after NP (T1-7).The rats were sacrificed after the measurement of pain threshold at T7 and their lumbar enlargements were removed to detect the expression of Cav3.2 mRNA and protein using Western blot and RT-PCR.Results Compared with group S,MWT was significantly decreased,TWL was shortened and the expression of Cav3.2 mRNA and protein was up-regulated in NP,D and K1-3 groups (P ＜ 0.05).Compared with NP group,MWT was significantly increased,TWL was prolonged and the expression of Cav3.2 mRNA and protein was down-regulated in a concentration-dependent manner in K1-3 groups (P ＜ 0.05),and no significant change was found in the parameters mentioned above in group D (P ＞ 0.05).Conclusion CaMK Ⅱ is involved in the development and maintenance of chronic NP by up-regulating the expression of Cav3.2 T-type calcium channels in rat spinal cord.
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ObjectiveTo establish a rat model of nerve damage induced by intrathecal(IT) lidocaine.MethodsFifty-five adult male SD rats weighing 200-220 g were randomly divided into 5 groups (n =11 each):group normal control (group C); group dimethyl sulfoxide (DMSO)-the solvent(group D) and groups IT 5％,10％,15％ lidocaine (groups L5.10.15 ).IT catheter was successfully implanted without complication in groups D,L5,L1o,L15.DMSO,5％,10％ and 15％ lidocaine 20 μl were injected IT in groups D,L5,L10,L15 respectively.Motor dysfunction of hindlimb was assessed and scored (0 =normal,2 =complete block) and paw withdrawal threshold to mechanical stimulation (von Frey filaments) (MWT) and paw withdrawal latency to thermal nociceptive stimulus (TWL) were measured before (baseline) and at 1,2,3,4,5,7 d after IT administration in 8 animals in each group.Three animals in each group were sacrificed at 1 d after IT administration.The lumbar segment (L4-5) was removed for microscopic examination.ResultsThere was no significant difference in motor dysfunction score,MWT and TWL among groups C,D and L5.MWT was significantly increased and TWL prolonged at 1 and 2 d after IT administration in group L10,while in group L15 motor dysfunction score was significantly increased at 1,2 d after IT administration and MWT was significantly increased and TWL prolonged at 1,2,3 d after IT administration.There was significant histologic damage to spinal cord in groups L10 and L15.Conclusion Nerve damage can be induced by IT 10％ lidocaine.
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Objective To investigate the effect of different doses of dexmedetomidine(Dex)on sevoflurane consumption in patients undergoing laparoscopic oophorocystectomy.Methods Eighty ASA Ⅰ or Ⅱ patients aged 25-50 yr with body mass index 18-25 kg/m2 undergoing laparoscopic oophorocystectomy were randomly divided into 4 groups (n =20): control group (group C),low dose Dex group(group DL),medium dose Dex group(group DM) and high dose Dex group(group DH).Normal saline 20 ml and Dex 0.3,0.6,0.9μg/kg was infused iv over 10 min at 10 min before skin incision in groups C,DL,DM and DH,respectively.End-tidal sevoflurane concentration (ETsev) was recorded before Dex administration(T1 ),skin incision(T2 ),immediately after pneumoperitoneum (T3 ),10 min of pneumoperitoneum(T4 ) and the end of surgery (T5 ).Duration of anesthesia,consumption of sevoflurane,emergence time,extubation time were recorded and restlessness at 10 min after extubation was also recorded.The concentrations of blood glucose and corticosteroid were measured by quickly by glucose analyzer and radio-immunity gefore anethesia induction (T0) and at T3,T4,T5 respectively.Results The consumption of sevoflurane per hour,ETsev at T2-5,concentrations of blood glucose and corticosteroid at T3-5 were decreased gradually in groups C,DL,DM and DH ( P ＜ 0.05).The emergence time and extubation time were shorter and the incidence of restlessness was lower in groups DL,DM and DH than in group C ( P ＜ 0.05 ).Conclusion Dexmedetomidine can reduce the consumption of sevoflurane in a dose-dependent manner in patients undergoing laparoscopic oophorocystectomy.
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Objective To investigate the effect of intrathecal (IT) dexmedetomidine on the expression of cAMP response element-binding protein phosphorylation (p-CREB) in spinal dorsal horn in a rat model of bone cancer pain. Methods Sixty-four adult female Wistar rats weighing 200-240 g were randomly divided into 4 groups (n = 16 each): sham operation group (group S); bone cancer pain group (group BP); normal saline group ( group NS) ; dexmedetomidine group (group D) . Bone cancer pain was induced by injecting Walker 2S6 mammary gland carcinoma cell suspension (2 ×106 cells/ml) 10μl into the medullary cavity of the tibia in BP, NS and D groups. Groups S and BP received no IT injection. Croups NS and D received IT injection of NS 10 μl and dexme detomidine 5 μg/kg respectively 7 days after successful establishment of the model. Ten animals were selected from each group at 1 day before IT administration (T0), immediately before IT administration (T1 ) and at 1, 6, 12 and 24 h after IT administration (T2-5 ) and paw withdrawal threshold (PWT) to mechanical stimuli was measured with von Frey filaments. The other 6 rats in each group were sacrificed at T4 and the spinal cord was removed for determination of p-CREB expression in the spinal dorsal horn.Results PWT was significantly decreased at T1-5 and pCREB expression up-regulated at T4 in BP, NS and D groups compared with group S ( P ＜ 0.05) . Compared with group BP, PWT was significantly decreased at T2-5 and p-CREB expression down-regulated at T4 in group D ( P ＜0.03), while no significant change in PWT and p-CREB expression was found in group NS (P ＞ 0.05) .Conclusion IT dexmedetomidine can reduce the bone cancer pain through inhibiting the phosphorylation of CREB in rat spinal dorsal horn.
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Objective To construct rat TRESK gene recombinant adenovirus expression vector.Methods TRESK full-length cDNA was cloned from rat dorsal root ganglion cells and confirmed by RT-PCR and sequencing. pAd/CMV/V5-DEST-TRESK was then constructed under the control of CMV-promotor. DH5α colibacillus was translated and the positive recombinants were subsequently identified by PCR and DNA sequencing. 293T cells were cotransfected and packed to produce adenovirus. Results The titer of virus was tested using Hole-by-dilution titer method. The full length of TRESK from rat dorsal root ganglion cells is 781 bp. It was demonstrated that the DNA sequencing was completely consistent with TRESK sequencing of rat recorded in GeneBank. The PCR amplification of the pAd/CMV/V5-DEST-TRESK gDNA was matched with pAD-GFP blank vector as anticipated. The titer of the concentrated virus was 1.31×109 TU/ml. Conclusion Rat TRESK gene recombinant adenovirus vector is constructed successfully.
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Objective To evaluate the changes in the expression of diplopore potassium ion channel TRESK mRNA in dorsal root ganlion (DRG) in rats with neuropathic pain (NP) .Methods Thirty-two male SD rats weighing 220-250 g were randomly divided into 2 groups ( n = 16 each) : group sham operation (group S) and group NP. NP was induced by ligation and severance of left tibial and common fibular nerves according to the technique described by Decosterd. Eight rats in each group were sacrificed 1 day before and 14 day after operation and their L4,5 DRGs in the operated side were isolated for determination of TRESK mRNA expression by RT-PCR. In the remaining 8 rats in each group paw withdrawal threshold to mechanical stimuli ( MWT) and paw withdrawal latency to a thermal nociceptive stimulus (TWL) were measured at 1 day before (baseline) and 1, 3, 5, 7, 14 day after operation. Results MWT was significantly lower in group NP than in group S. The TRESK mRNA expression in L4,5 DRGs in the operated side was significantly decreased after operation as compared with the baseline before operation in group NP and was significantly lower in group NP than in group S. Conclusion The development and maintenance of NP may be closely related with down-regulation of TRESK mRNA.
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Objective To determine the half-effective target plasma concentration(EC50)of remifentanil inhibiting airway response when combined with propofol by TCI in patients undergoing fiberoptic bronchoscopy.Methods Forty ASAⅠorⅡ patients,aged 20-64 yr, undergoing elective fiberoptic bronchoscopy, were randomly divided into 2 groups (n = 20 each).Anesthesia was performed with TCI of remifentanil and propofol in both groups. The target effect site concentration of propofol was 3 μg/ml.The target effect site concentration of remifentanil was determined by up-and-down sequential hial. The target effect site concentration of remifentanil was set at 5 μg/ml in the first patient and the ratio of the target concentrations between the two consecutive patients was 1.1. BIS ≤ 60 was defined as the suitable depth of anesthesia in group A.The airway response≤grade Ⅱ was defined as the suitable depth of anesthesia in group B. The EC50 and 95% confidence interval (CI) required to inhibit the airway response were calculated in the two groups.Results The EC50 and 95% CI of remifentanil required to inhibit the airway response were 4.50μg/L (95% CI 3.88-5.36 μg/L)in group A and 4.10μg/L(95% GI 3.31-5.00 μg/L) in group B. The EC50 of remifentanil inhibiting airway response was significantly higher in group A than in group B. Conclusion The EC50 of remifentanil inhibiting airway response is 4.10 μg/L when combined with propofol by TGI (effect site concentration 3μg/ml)in patients undergoing bronchoscopy. BIS is not a suitable index assessing the depth of propofol-remifentanil anesthesia.