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Objective:To evaluate the effect of intrathecal insulin-like growth factor-1 (IGF-1) on chemotherapy-induced neuropathic pain (NP) in mice.Methods:Forty clean-grade healthy male C57 mice, aged 7-9 weeks, weighing 22-24 g, were divided into 4 groups ( n=10 each) using a random number table method: control group (group C), chemotherapy-induced NP group (group CIPN), low-dose IGF-1 group (group I1) and high-dose IGF-1 group (group I2). In CIPN, I1 and I2 groups, oxaliplatin 5 mg/kg was intraperitoneally injected for 5 consecutive days to establish chemotherapy-induced NP model.Normal saline 0.2 ml was given in group C. After measurement of the pain threshold at 10 days after establishment of the model, IGF-1 0.5 and 1.0 μg were intrathecally injected in group I1 and group I2, respectively.Normal saline 5 μl was intrathecally injected in C and CINP groups.Mechanical withdrawal threshold (MWT) was measured at 3, 5, 8, 10, 11, 13 and 15 days after establishment of the model.After measurement of the pain threshold at 15 days after establishment of the model, the expression of spinal IGF-1, IGF-1receptor (IGF-1R), interleukin (IL)-17A, IL-1β and tumor necrosis factor (TNF)-α was detected, and IGF-1 positive cells were counted using immunofluorescence. Results:Compared with group C, MWT was significantly decreased, the expression of spinal IGF-1 was down-regulated, the count of IGF-1 positive cells was decreased, and expression of IL-17A, IL-1β and TNF-α was up-regulated at 3-25 days after establishment of the model in CINP, I1 and I2 groups ( P<0.05). Compared with group CIPN, MWT was significantly increased at 15 days after establishment of the model in group I1, and MWT was increased, the expression of spinal IGF-1 was up-regulated, the count of IGF-1 positive cells was increased, and expression of IL-17A, IL-1β and TNF-α was down-regulated at 13 and 15 days after establishment of the model in group I2 ( P<0.05). Compared with group I1, the count of IGF-1 positive cells in spinal dorsal horn was increased in group I2 ( P<0.05). There was no significant difference in the expression of spinal IGF-1R among the 4 groups ( P>0.05). Conclusion:Intrathecal IGF-1 can alleviate chemotherapy-induced NP, and the mechanism may be related to inhibiting the inflammatory responses in spinal cord of mice.
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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 role of spinal cord tumor necrosis factor receptor-associated factor 6 (TRAF6)/nuclear factor kappa B (NF-κB)signaling pathway in the development of diabetic neuropathic pain (DNP)in rats.Methods Clean-grade healthy adult male Sprague-Dawley rats,aged 2 months,weighing 180-230 g,in which IT catheters were implanted,were used in this study.Streptozotocin 60 mg/kg was intraperitoneally injected after IT catheterization to establish the model of DNP.Twelve DNP rats were divided into 2 groups (n =6 each) by a random number table method:DNP group and DNP plus TRAF6 inhibitor group (group DTR).Another 6 age-matched Sprague-Dawley rats were used as normal control group (group NC).The rats in group DC and group DTR received IT injection of dimethyl sulfoxide 10 μl and TRAF6 inhibition 10 μg,respectively,once a day for 7 consecutive days starting from day 21 after establishing the model.The mechanical paw withdrawal threshold (MWT) was determined before establishing the model (T1),on 7,14 and 21 days after establishing the model (T2-4),and on 1,4 and 7 days after IT injection (T5-7).The rats were sacrificed after the last MWT measurement,and the L3-5 segments of the spinal cord were removed for determination of the expression of TRAF6 and NFκB p65 by Western blot.Results Compared with group NC,the MWT at T3-7 in group DC and at T3-6 in group DTR was significantly decreased,and the expression of spinal TRAF6 and NF-κB p65 was up-regulated in DC and DTR groups (P＜0.05).Compared with group DC,the MWT was significantly increased at T6-7,and the expression of spinal TRAF6 and NF-κB p65 was down-regulated in group DTR (P ＜ 0.05).Conclusion Spinal cord TRAF6/NF-κB signaling pathway is involved in the development of DNP in rats.
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Objective To evaluate the role of microRNA9 (miR-9) in spinal dorsal horn neurons in over-expression of calcium homeostasis modulator 1 (CALHM1) in rats with diabetic neuropathic pain (DNP).Methods Ninety-three healthy male Sprague-Dawley rats,aged 2 months,weighing 180-200 g,were used in the study.Diabetes mellitus was induced by intraperitoneal 1％ streptozocin (STZ) 60 mg/kg.The experiment was performed in two parts.Experiment Ⅰ The rats were divided into control group (group C,n=10) and DNP group (n=83) using a random number table.The mechanical paw withdrawal threshold (MWT) was measured before STZ injection and at 1,2,3,4,5 and 6 weeks after STZ injection.The expression of miR-9 in the spinal dorsal horn was determined using the in situ hybridization at 6 weeks after STZ injection.Experiment Ⅱ The rats with DNP were selected at 6 weeks after STZ injection,and the spinal dorsal horn neurons were isolated and cultured.The neurons were seeded in culture plates at the density of 5×106 cells/ml (2 ml/well) and divided into 2 groups (n=18 each) using a random number table:control group (group C) and miR-9 antisense oligonucleotide group (group ASO).The neurons were cultured in normal culture atmosphere in group C.In group ASO,the single nucleotide sequence of miR-9 antisense oligonucleotide sequence 5'-UUCUCCGAACGUGUCACGUTT-3'was added with the final concentration of 100 pmol/L.The expression of miR-9 and CALHM1 mRNA was detected using quantitative real-time polymerase chain reaction at 48 h of incubation.The expression of CALHM1 was detected by Western blot at 72 h of incubation.Results Experiment Ⅰ Compared with group C,the MWT was significantly decreased at 2-6 weeks after STZ injection,and the expression of miR-9 in the spinal dorsal horn was up-regulated in group DNP (P＜0.05).Experiment Ⅱ Compared with group C,the expression of miR-9 and CALHM1 protein and mRNA in spinal dorsal horn neurons was significantly down-regulated in group ASO (P＜0.05).Conclusion miR-9 in spinal dorsal horn neurons probably mediates the over-expression of CALHM1 in rats with DNP.
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Objective To evaluate the effect of intrathecal cardamonin on diabetic neuropathic pain (DNP) in rats.Methods Healthy adult male Sprague-Dawley rats,aged 2 months,weighing 180-220 g,were included in the study.Diabetes mellitus was produced by intraperitoneal injection of streptozotocin 60 mg/kg after intrathecal catheterization.When decrease in pain threshold＞50％ of the baseline at 21 days after diabetes mellitus was produced,the induction of DNP was considered successful.Twenty-four rats with DNP were divided into 4 groups (n=6 each) using a random number table:group DNP,rapamycin group (group R),cardamonin 50 μg group (group D50) and cardamonin 100 μg group (group D100).Another 6 healthy age-matched rats were used as normal control (group C).In DNP,R,D50 and D100 groups,dimethyl sulfoxide 10 μl,rapamycin 5 μg and cardamonin 50 μg and 100 μg were intrathecally injected,respectively,once a day for 7 consecutive days starting from 21 days after successful estabiishment of the model.Mechanical paw withdrawal threshold (MWT) was measured before establishment of the model,on 7,14 and 21 days after establishment of the model,and on 1,4 and 7 days after intrathecal injection.The rats were sacrificed after the last MWT measurement,and their L3-5 segments of the spinal cord were removed for determination of the expression of S6K,p-S6K and synapsin Ⅱ by Western blot.Results Compared with group C,MWT was significantly decreased,and the expression of spinal S6K,p-S6K and synapsin Ⅱ was up-regulated in group DNP (P＜0.05 or 0.01).Compared with group DNP,MWT was significantly increased,and the expression of spinal S6K,p-S6K and synapsin Ⅱ was down-regulated in R,D50 and D100 groups (P＜0.05 or 0.01).Compared with group D50,MWT was significantly increased,and the expression of spinal S6K,p-S6K and synapsin Ⅱ was down-regulated in group D100 (P＜0.05).Conclusion Intrathecal cardamonin can relieve DNP in rats,and the mechanism is related to inhibiting spinal mammalian target of rapamycin activity and down-regulating the expression of synapsin Ⅱ.
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Objective To investigate the role of phosphatase and tensin homologue deleted on chromosome 10 (PTEN) protein in the spinal cord neurons in diabetic neuropathic pain (DNP) in rats.Methods Male Sprague-Dawley rats,aged 2 months,weighing 180-200 g,were studied.Diabetes mellitus was induced by single intraperitoneal injection of streptozotocin (STZ) 60 mg/kg.Sixteen rats with DNP were randomly divided into 2 groups (n =8 each) using a random number table:DNP group and DNP+PTEN inhibitor bpv (pic) group (DPN-bpv group).Another 16 rats were equally and randomly divided into either control group (group C) or bpv group.In DNP-bpv and bpv groups,bpv (pic) 0.2mg/kg was injected intraperitoneally once a day within 14-28 days after injection of STZ.Before STZ injection (T1),and at 2,7,14,21 and 28 days after STZ injection (T2-6),the mechanical paw withdrawal threshold (MWT) was measured.After measurement of MWT,the rats were sacrificed,and the lumbar segments of the spinal cord (L4.5) were removed for determination of PTEN protein activity (by ELISA) and Akt (s473) phosphorylation (by Western blot).Results Compared with group C,the MWT was significantly decreased at T4-6,and the PTEN protein activity and Akt (s473) phosphorylation were significantly increased in DNP and DNP-bpv groups (P＜0.05 or 0.01).Compared with group DNP,the MWT was significantly increased at T6,and the PTEN protein activity and Akt (s473) phosphorylation were significantly decreased in group DNP-bpv (P＜0.05).Conclusion PTEN protein in the spinal cord neurons is involved in the maintenance of DNP in rats.
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Objective To investigate the effect of propofol on human renal tubule epithelial cell (HK-2 cells) fibrosis induced by ATP depletion/recovery and the role of transforming growth factor β activated kinase 1 (TAK1) in it.Methods HK-2 cells were seeded in 96-well plates,and randomly divided into 4 groups (n =36 each) using a random number table:control group (group C),ATP depletion/recovery group (group D/R),propofol group (group P),and TAK1 over-expression group (group T).HK-2 cells were exposed to antimycin A for 1 h and then returned to normal culture medium to establish the model of ATP depletion/recovery-induced injury.At 1 h before ATP depletion,the cells were incubated for 1 h in the DMEM liquid culture medium containing propofol with the final concentration of 20 μmol/L in group P,and the cells were incubated for 1 h in the DMEM liquid culture medium containing propofol with the final concentration of 20 μmol/L and TAK1 with the titer of 2× 107 TU/ml in group T,and the other treatments were similar to those previously described in group D/R.At 12 h after ATP recovery,the cell viability was evaluated by methyl thiazolyl tetrazolium assay,and cell apoptosis was detected using TUNEL and scored.The expression of TAK1 was detected using Western blot at 12,24 and 48 h after ATP recovery.The expression of α-smooth muscle actin (αSMA),fibronectin (FN),and collagen protein 1 (COL1) was measured at 48 h after ATP recovery.Results Compared with group C,the cell viability was significantly decreased,the apoptosis score was increased,and the expression of TAK1,COL1,αSMA and FN was up-regulated after ATP recovery in D/R,P and T groups (P＜0.05).Compared with group D/R,the cell viability was significantly increased,the apoptosis score was decreased,and the expression of TAK1,COL1,αSMA and FN was down-regulated after ATP recovery in P and T groups (P＜0.05).Compared with group P,the cell viability was significantly decreased,the apoptosis score was increased,and the expression of TAK1,COL1,αSMA and FN was up-regulated after ATP recovery in group T (P＜ 0.05).Conclusion Propofol can reduce HK-2 cell fibrosis induced by ATP depletion/recovery,and the mechanism may be related to down-regulation of TAK1 expression.
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Objective To compare the anesthetic efficacy of ketamine and sevoflurane for foreskin ligation in the pediatric patients.Methods A total of 120 pediatric patients,aged 2-6 yr,weighing 10-18 kg,scheduled for elective foreskin ligation,were equally and randomly divided into ketamine group (group K) and sevoflurance group (group S).In group K,atropine 0.25 mg/kg and ketamine 2 mg/kgwere injected intravenously,and foreskin ligation was performed after loss of eyelash reflex.In group S,8％ sevoflurance was inhaled using the tidal volume technique,the concentration inhaled was adjusted to 4％ after loss of eyelash reflex,and then foreskin ligation was performed.The occurrence of crying before and during anesthesia induction,induction time,emergence time,occurrence of agitation during emergence from anesthesia and duration of agitation were recorded.Results Compared with group K,the rate of crying was significantly decreased,the emergence time was shortened (P＜0.05),and no significant difference was found in the induction time,incidence of agitation during emergence from anesthesia,and duration of agitation in group S (P＞0.05).Conclusion Sevoflurance provides better anesthetic efficacy than ketamine when applied for foreskin ligation in the pediatric patients.
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Objective To evaluate the effect of intrathecal rapamycin on diabetic neuropathic pain in rats.Methods Thirty adult male Sprague-Dawley rats,weighing 180-220 g,in which IT catheters were successfully implanted,were randomly divided into 5 groups (n =6 each) using a random number table:control group (group C),diabetic neuropathic pain group (group DN),rapamycin 1 μg group (group R1),rapamycin 3 μg group (group R3) and rapamycin 10 μg (group R10).Diabetes mellitus was induced by intraperitoneal streptozotocin (STZ) 60 mg/kg on 5 days after IT catheters were implanted in DN,R1,R3 and R10 groups.Citric acid-sodium citrate buffer 6 ml/kg was injected intraperitoneally in group C.In R1,R3 and R10 groups,rapamycin (dissolved in 10 μl 4％ dimethyl sulfoxide) 1,3 and 10 μg were intrathecally injected,respectively,once a day for 7 consecutive days starting from day 21 after STZ injection,while the equal volume of 4％ dimethyl sulfoxide was given instead in C and DN groups.Paw withdrawal threshold (PWT) to yon Frey filament stimulation was measured before IT catheters were implanted,before STZ injection,on 7,14 and 21 days after STZ injection,and on 1,3,5 and 7 days after rapamycin administration.After measurement of PWT,the rats were sacrificed and L2-5 segments of the spinal cord were removed for determination of the expression of mTOR and phosphorylated mTOR (p-mTOR),S6K and phosphorylated S6K (p-S6K) (by Western blot) and expression of mTOR mRNA and S6K mRNA (by RT-PCR).Results Compared with group C,MWT was significantly decreased at 14 and 21 days after STZ injection in DN,R1,R3 and R10 groups,and the expression of mTOR,p-mTOR,S6K,p-S6K,mTOR mRNA and S6K mRNA was up-regulated in group DN (P ＜ 0.01).Compared with group DN,MWT was significantly increased at 5 and 7 days after rapamycin administration in group R1,at 3,5 and 7 days after rapamycin administration in group R3,and at 1,3,5 and 7 days after rapamycin administration in group R10,and the expression of mTOR,p-mTOR,S6K,p-S6K,mTOR mRNA and S6K mRNA was down-regulated in R1,R3 and R10 groups (P ＜ 0.01).Conclusion Intrathecal rapamycin can alleviate diabetic neuropathic pain in rats.
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Objective To evaluate the changes in autophagy in spinal neurons of rats with diabetic neuropathic pain (DNP).Methods Forty-eight male Sprague-Dawley rats,weighing 220-250 g,were randomly divided into control group (group C,n =8) and group DNP (n =40) using a random number table.Diabetes mellitus was induced by a single intraperitoneal injection of streptozotocin (STZ) 60 mg/kg.Before STZ injection and at 1,2,4,and 8 weeks after STZ injection,8 rats randomly chosen from each group were used to measure mechanical pain threshold.The animals were sacrificed after measurement of mechanical pain threshold and the spinal cords were removed for determination of the expression of LC3-Ⅰ,LC3-Ⅱ,Beclin-1 and p62 protein.LC3-Ⅱ/LC3-Ⅰ ratio was calculated.Results Compared with group C,mechanical pain threshold was significantly decreased at 2,4,and 8 weeks after STZ injection in group DNP.The expression of LC3-Ⅱ and Beclin-1 in the spinal cord was significantly up-regulated,p62 protein expression was down-regulated,and LC3-Ⅱ/LC3-Ⅰ ratio was increased at 2,4,and 8 weeks after STZ injection as compared with the baseline value before STZ injection in group DNP.Conclusion Enhanced autophagy in spinal neurons may be involved in the development and maintenance of DNP in rats.
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Objective To evaluate the role of mTOR in spinal cord in the development of diabetic neuropathic pain in rats.Methods Sixty adult male Sprague-Dawley rats,aged 2 months,weighing 180-220 g,were used in the study.Forty-five rats among them were chosen randomly and diabetes mellitus was induced by intraperitoneal streptozotocin (STZ) 60 mg/kg and confirmed by blood glucose ＞ 16.7 mmol/L on day 3 after STZ injection.The left 15 rats received intraperitoneal injection of the equal volume of citric acid-sodium citrate buffer and served as normal control group (group C).Paw withdrawal threshold to von Frey filament stimulation was measured in the right hind paw before STZ injection and on 3,6,9,12,15,18,and 21 days after STZ injection.The diabetic rats with mechanical pain threshold decreasing by more than 50％ of the baseline were allocated to diabetic neuropathic pain group (group DP),and by less than 25 ％ of the baseline were allocated to diabetic non-neuropathic pain group (group NP).The rats were sacrificed at 21 days after STZ injection,and their lumbar enlargements of the spinal cord were removed for determination of the expression of mTOR and phosphorylated mTOR (p-mTOR) by Western blot.Results The expression of mTOR was significantly up-regulated in DP and NP groups when compared with group C (P ＜ 0.05),the expression of p-mTOR was up-regulated in DP group,and no significant change was found in the expression of p-mTOR in group NP (P ＞ 0.05).Compared with group NP,the expression of p-mTOR was significantly up-regulated (P ＜ 0.05),and no significant change was found in the expression of mTOR in group DP (P ＞ 0.05).Conclusion Activation of mTOR in the spinal cord is involved in the development of diabetic neuropathic pain in rats.
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Objective To evaluate the role of nitric oxide (NO) in the spinal cord in the maintenance of diabetic neuropathic pain in rats.Methods Male Sprague-Dawley rats,aged 2 months,weighing 180-200 g,were used in the study.Diabetes mellitus was induced by intraperitoneal streptozotocin (STZ) 60 mg/kg and confirmed by blood glucose ＞ 16.7 mmol/L on day 2 after STZ injection.Twenty diabetic rats were randomly allocated into diabetes mellitus group (DM group,n =10) and L-NAME (non-selective NOS inhibitor) group (LN group,n =10).Another 10 age-matched normal rats served as control group (C group).On 21 days after STZ injection,L-NAME 10 mg/kg was injected intraperitoneally once a day for 7 consecutive days in LN group,whereas the equal volume of normal saline 5 ml/kg was given instead of L-NAME in DM group.Paw withdrawal threshold to yon Frey filament stimulation (PWT) was measured before STZ infection and on 7,14,21 and28 days after STZ injection.The rats were sacrificed after the last measurement of PWT and the lumbar segments of spinal cord were removed for determination of NO content and neuronal nitric oxide synthase (nNOS) expression (by Western blot analysis) in spinal cord tissues.Results Compared with C group,PWT was significantly decreased on 14,21 and 28 days after STZ injection,and the NO content and nNOS expression in spinal cord tissues were increased in DM and LN groups (P ＜ 0.05).Compared with DM group,PWT was significantly increased on 28 days after STZ injection,and the NO content and nNOS expression in spinal cord tissues were decreased in LN group (P ＜ 0.05).Conclusion NO in the spinal cord is involved in the maintenance of diabetic neuropathic pain in rats and the mechanism is related to the enhanced function of nNOS.
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Objective To compare the quality of emergence from TCI of sufentanil and remifentanil supplementing propofol-sevoflurane anesthesia in patients undergoing radical colo-rectal cancer resection.Methods Forty ASA Ⅰ or Ⅱ patients of both sexes aged 40-64 yr undergoing elective radical colo-rectal cancer resection were allocated into 2 groups ( n =20 each):sufentanil group (group S) and remifentanil group (group R).Anesthesia was induced with propofol TCI at plasma concentration (Cp) of 4.0 μg/ml in both groups and sufentanil TCI (effect-site concentration Ce =0.4 ng/ml ) or remifentanil TCI ( Cp =4.0 ng/ml).Tracheal intubation was facilitated with vecuronium 0.1 mg/kg.The patients were mechanically ventilated (VT =8-10 ml/kg,RR =12-16 bpm).PErCO2 was maintained at 30-40 mm Hg.Anesthesia was maintained with propofol TCI-sevoflurane supplemented with sufentanil (Ce=0.25 ng/ml) or remifentanil (Cp=2.5 ng/ml).The depth of anesthesia was maintained at Narcotrend index of 37-56 by adjusting Cp of propofol TCI and sevoflurane concentration.The infusion of sufentanil was discontinued at 40 min before the conclusion of the operation while remifentanil was administered until the end of surgery.The incidence of postoperative adverse events,the time from the end of operation to eye openg and the time to extubation were recorded.Reesults The two groups were comparable with respect to demographic data.Neither group developed prolonged emergence and respiratory depression but the time from the end of operation to eye opening and the time to extubation were significantly longer in group S than in group R.The incidence of hypertension and tachycardia,agitation,shivering aad coughing were significantly lower in group S than in group R.Conclusion The quality of emergence from sufentanil supplementing propofol-sevoflurane anesthesia is higher than that from remifentanil.