Dorsal root ganglion （DRG） neurons from newborn Wistar rats cultured in vitro were pressurized with 20, 40, 80 or 120 mm Hg compressive Ioadings （1 mm Hg = 0.133 kPa） for 12, 24, 48 or 72 hours, respectively. The ...Dorsal root ganglion （DRG） neurons from newborn Wistar rats cultured in vitro were pressurized with 20, 40, 80 or 120 mm Hg compressive Ioadings （1 mm Hg = 0.133 kPa） for 12, 24, 48 or 72 hours, respectively. The 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide test showed that pressures less than 80 mm Hg had no obvious impact on the activity of DRG neurons. The protein expression levels of transient receptor potential vanilloid receptor 4 （TRPV4）, transient receptor potential vanilloid receptor 1, transient receptor potential channel of melastatin type 8, and transient receptor potential subtype ankyrin 1 were assessed by western blot analysis. The mRNA expression of TRPV4 was assessed by real-time PCR. The results showed that sustained mechanical compression up-regulated TRPV4 mRNA and protein expression in the rat DRG neurons, in a time-dependent fashion. Similar changes were not found in the protein expression of transient receptor potential vanilloid receptor 1, transient receptor potential channel of melastatin type 8, and transient receptor potential subtype ankyrin 1. Images of cells using a laser scanning confocal microscope showed that the sustained mechanical pressure increased the number of responsive DRG neurons and was synergistic on the enhanced Ca^2＋ responses to the TRPV4 phorbol ester agonist 4a-phorbo112, 13-didecanoate and hypotonic solutions. These findings demonstrate that sustained mechanical compressive loading in vitro increases the expression of TRPV4 mRNA and protein in DRG neurons and sensitizes TRPV4 Ca^2＋ signals. Mechanical compression does not impact other ion channels in the transient receptor potential family.展开更多
By in situ hybridization histochemistry, the changes of preprotachykinin (PPT) mRNA expression were examined in the neurons of adjacent thoracal dorsal root ganglion (DRG) after a strong electric stimulation to an int...By in situ hybridization histochemistry, the changes of preprotachykinin (PPT) mRNA expression were examined in the neurons of adjacent thoracal dorsal root ganglion (DRG) after a strong electric stimulation to an intact dorsal cutaneous branch and the cut distal part of left T 9 thoracal spinal nerve of rat. There was a significant increase of the number of neurons expressing PPT mRNA in the ipsilateral T 8, T 9 and T 10 DRG of the animals given electric stimulation to intact spinal nerve branch 24 h after the electric stimulation. The same increase was found in the ipsilateral T 8 and T 10 DRG of the animals given electric stimulation to the distal part of spinal nerve branch. While no change was found in the DRG of the contralateral side of these animals. The present results showed that the antidromic electric stimulation strengthened the biosynthesis of PPT mRNA in adjacent DRG. These findings suggested that there was information transmission across segments between two sensory nerve endings and some bioactive substances such as SP might play important roles in the information transmission across segments of spinal cord.展开更多
End-to-side neurorrhaphy is an option in the treatment of the long segment defects of a nerve.It involves suturing the distal stump of the disconnected nerve（recipient nerve） to the side of the intimate adjacent ne...End-to-side neurorrhaphy is an option in the treatment of the long segment defects of a nerve.It involves suturing the distal stump of the disconnected nerve（recipient nerve） to the side of the intimate adjacent nerve（donor nerve）.However,the motor-sensory specificity after end-to-side neurorrhaphy remains unclear.This study sought to evaluate whether cutaneous sensory nerve regeneration induces motor nerves after end-to-side neurorrhaphy.Thirty rats were randomized into three groups：（1） end-to-side neurorrhaphy using the ulnar nerve（mixed sensory and motor） as the donor nerve and the cutaneous antebrachii medialis nerve as the recipient nerve;（2） the sham group：ulnar nerve and cutaneous antebrachii medialis nerve were just exposed;and（3） the transected nerve group：cutaneous antebrachii medialis nerve was transected and the stumps were turned over and tied.At 5 months,acetylcholinesterase staining results showed that 34% ± 16% of the myelinated axons were stained in the end-to-side group,and none of the myelinated axons were stained in either the sham or transected nerve groups.Retrograde fluorescent tracing of spinal motor neurons and dorsal root ganglion showed the proportion of motor neurons from the cutaneous antebrachii medialis nerve of the end-to-side group was 21% ± 5%.In contrast,no motor neurons from the cutaneous antebrachii medialis nerve of the sham group and transected nerve group were found in the spinal cord segment.These results confirmed that motor neuron regeneration occurred after cutaneous nerve end-to-side neurorrhaphy.展开更多
目的建立大鼠慢性坐骨神经压迫(CCI)模型,探讨蛇床子素对CCI大鼠背根神经节(DRG)中髓样分化因子88(MyD88)、磷酸化细胞外信号调节激酶(p-ERK)表达的影响。方法24只SD大鼠随机分为3组:假手术(sham)组,CCI组,治疗组,每组8只。治疗组分别...目的建立大鼠慢性坐骨神经压迫(CCI)模型,探讨蛇床子素对CCI大鼠背根神经节(DRG)中髓样分化因子88(MyD88)、磷酸化细胞外信号调节激酶(p-ERK)表达的影响。方法24只SD大鼠随机分为3组:假手术(sham)组,CCI组,治疗组,每组8只。治疗组分别于术前1 d、术后1、7 d鞘内注射蛇床子素(1 mg/50μL),sham组、CCI组在相同给药时间注射相同体积生理盐水。各组大鼠分别在术后1、3、5、7、14 d检测后足机械缩足阈值(PMWT)和后足热缩足反射潜伏期(PTWL)。使用Western blotting检测大鼠DRG中MyD88和p-ERK表达。结果与sham组大鼠比较,CCI组大鼠的PMWT明显降低(P<0.01)。与CCI组比较,治疗组大鼠术后1、3、5 d PMWT没有统计学差异(P>0.05),而术后7、14 d PMWT明显升高(P<0.05)。与sham组比较,CCI组的大鼠PTWL明显缩短(P<0.01);与CCI组比较,治疗组PTWL明显增加(P<0.01)。与sham组比较,CCI组术后14 d DRG中My D88、p-ERK表达明显增加(P<0.05);与CCI组比较,治疗组术后14 d DRG中MyD88、p-ERK表达量明显减少(P<0.05)。结论蛇床子素可下调CCI大鼠DRG中MyD88的表达,减轻神经病理性疼痛。展开更多
基金the National Natural Science Foundation of China (General Program),No. 30872732the National Natural Science Foundation of China for Youths,No.81101453
文摘Dorsal root ganglion （DRG） neurons from newborn Wistar rats cultured in vitro were pressurized with 20, 40, 80 or 120 mm Hg compressive Ioadings （1 mm Hg = 0.133 kPa） for 12, 24, 48 or 72 hours, respectively. The 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide test showed that pressures less than 80 mm Hg had no obvious impact on the activity of DRG neurons. The protein expression levels of transient receptor potential vanilloid receptor 4 （TRPV4）, transient receptor potential vanilloid receptor 1, transient receptor potential channel of melastatin type 8, and transient receptor potential subtype ankyrin 1 were assessed by western blot analysis. The mRNA expression of TRPV4 was assessed by real-time PCR. The results showed that sustained mechanical compression up-regulated TRPV4 mRNA and protein expression in the rat DRG neurons, in a time-dependent fashion. Similar changes were not found in the protein expression of transient receptor potential vanilloid receptor 1, transient receptor potential channel of melastatin type 8, and transient receptor potential subtype ankyrin 1. Images of cells using a laser scanning confocal microscope showed that the sustained mechanical pressure increased the number of responsive DRG neurons and was synergistic on the enhanced Ca^2＋ responses to the TRPV4 phorbol ester agonist 4a-phorbo112, 13-didecanoate and hypotonic solutions. These findings demonstrate that sustained mechanical compressive loading in vitro increases the expression of TRPV4 mRNA and protein in DRG neurons and sensitizes TRPV4 Ca^2＋ signals. Mechanical compression does not impact other ion channels in the transient receptor potential family.
基金the National Natural Science Foundation of China(No.30470559,30330230,30240059)the National Basic Research Development Program(973)of China(No.2007CB512501)Beijing Natural Science Foundation(No.7052039)
文摘Dorsal root ganglion(DRG)neurons have peripheral terminals in skin,muscle,and other peripheral tissues,andcentral
文摘By in situ hybridization histochemistry, the changes of preprotachykinin (PPT) mRNA expression were examined in the neurons of adjacent thoracal dorsal root ganglion (DRG) after a strong electric stimulation to an intact dorsal cutaneous branch and the cut distal part of left T 9 thoracal spinal nerve of rat. There was a significant increase of the number of neurons expressing PPT mRNA in the ipsilateral T 8, T 9 and T 10 DRG of the animals given electric stimulation to intact spinal nerve branch 24 h after the electric stimulation. The same increase was found in the ipsilateral T 8 and T 10 DRG of the animals given electric stimulation to the distal part of spinal nerve branch. While no change was found in the DRG of the contralateral side of these animals. The present results showed that the antidromic electric stimulation strengthened the biosynthesis of PPT mRNA in adjacent DRG. These findings suggested that there was information transmission across segments between two sensory nerve endings and some bioactive substances such as SP might play important roles in the information transmission across segments of spinal cord.
文摘End-to-side neurorrhaphy is an option in the treatment of the long segment defects of a nerve.It involves suturing the distal stump of the disconnected nerve（recipient nerve） to the side of the intimate adjacent nerve（donor nerve）.However,the motor-sensory specificity after end-to-side neurorrhaphy remains unclear.This study sought to evaluate whether cutaneous sensory nerve regeneration induces motor nerves after end-to-side neurorrhaphy.Thirty rats were randomized into three groups：（1） end-to-side neurorrhaphy using the ulnar nerve（mixed sensory and motor） as the donor nerve and the cutaneous antebrachii medialis nerve as the recipient nerve;（2） the sham group：ulnar nerve and cutaneous antebrachii medialis nerve were just exposed;and（3） the transected nerve group：cutaneous antebrachii medialis nerve was transected and the stumps were turned over and tied.At 5 months,acetylcholinesterase staining results showed that 34% ± 16% of the myelinated axons were stained in the end-to-side group,and none of the myelinated axons were stained in either the sham or transected nerve groups.Retrograde fluorescent tracing of spinal motor neurons and dorsal root ganglion showed the proportion of motor neurons from the cutaneous antebrachii medialis nerve of the end-to-side group was 21% ± 5%.In contrast,no motor neurons from the cutaneous antebrachii medialis nerve of the sham group and transected nerve group were found in the spinal cord segment.These results confirmed that motor neuron regeneration occurred after cutaneous nerve end-to-side neurorrhaphy.
文摘目的建立大鼠慢性坐骨神经压迫(CCI)模型,探讨蛇床子素对CCI大鼠背根神经节(DRG)中髓样分化因子88(MyD88)、磷酸化细胞外信号调节激酶(p-ERK)表达的影响。方法24只SD大鼠随机分为3组:假手术(sham)组,CCI组,治疗组,每组8只。治疗组分别于术前1 d、术后1、7 d鞘内注射蛇床子素(1 mg/50μL),sham组、CCI组在相同给药时间注射相同体积生理盐水。各组大鼠分别在术后1、3、5、7、14 d检测后足机械缩足阈值(PMWT)和后足热缩足反射潜伏期(PTWL)。使用Western blotting检测大鼠DRG中MyD88和p-ERK表达。结果与sham组大鼠比较,CCI组大鼠的PMWT明显降低(P<0.01)。与CCI组比较,治疗组大鼠术后1、3、5 d PMWT没有统计学差异(P>0.05),而术后7、14 d PMWT明显升高(P<0.05)。与sham组比较,CCI组的大鼠PTWL明显缩短(P<0.01);与CCI组比较,治疗组PTWL明显增加(P<0.01)。与sham组比较,CCI组术后14 d DRG中My D88、p-ERK表达明显增加(P<0.05);与CCI组比较,治疗组术后14 d DRG中MyD88、p-ERK表达量明显减少(P<0.05)。结论蛇床子素可下调CCI大鼠DRG中MyD88的表达,减轻神经病理性疼痛。
