星状神经节阻滞对甲醛致痛兔血清皮质醇和炎症局部β-内啡肽的影响

背景星状神经节阻滞(stellate ganglion block,SGB)在疼痛治疗中较为常用,但其治疗疼痛的机制尚不十分清楚.目的研究星状神经节阻滞对甲醛炎症痛家兔血清皮质醇和炎症局部β-内啡肽含量的影响.设计随机对照的实验研究.地点和对象在郧阳医学院附属太和医院神经科学研究所进行实验,选择健康家兔16只,随机分为SGB组和对照组,各8只.干预用手术法在所有动物星状神经节处置入一导管.两组动物均用80 g/L甲醛溶液0.5 mL在右前肢足底皮下注射致痛,致痛前10 min SGB组经预置导管注入2.5 g/L布比卡因0.5 mL,对照组注入等量生理盐水.主要观察指标用放免法测定致痛前10 min、致痛后10,60和120 min血清皮质醇及致痛120 min炎症局部β-内啡肽含量.结果致痛后对照组血清皮质醇在各时点均较致痛前升高,且在致痛后60 min时达高峰(462.3±88.5)nmol/L],而SGB组各时点较致痛前(130.2±31.7)nmol/L]无明显差异;SGB组和对照组相比,致痛前10 min时无差异,而在致痛后10 min(146.3±54.8),(186.5±45.8)nmol/L,t=2.482, P＜0.05],致痛后60 min(138.4±32.5),(462.3±88.5)nmol/L,t=5.875,P＜0.01]和致痛后120 min时(140.9±55.6),(321.4±65.3)nmol/L,t=4.183,P＜0.01]有明显差异.SGB组致痛后120 min时炎症局部β-内啡肽含量(1675±343)pg/g]明显高于对照组(418±56)pg/g,t=7.133,P＜0.01].结论星状神经节阻滞可抑制甲醛溶液刺激引起的血清皮质醇的升高,并且可增加炎症局部B-内啡肽含量.

Effect of stellate ganglion block on serum cortisol and beta-endorphin in inflammatory tissue of rabbits with formalin-induced pain

BACKGROUND: Stellate ganglion block(SGB) is commonly used in pain therapy. However, the mechanisms of SGB in pain treatment are not well understood.OBJECTIVE: To investigate the effect of SGB on the concentration of serum cortisol and β-endorphin of inflammatory tissue in rabbits with formalin-induced pain.DESIGN: A randomized controlled experiment was conducted.SETTING and PARTICIPANTS: The experiment was performed in the Research Institute of Neuroscience, Taihe Hospital of Yunyang Medical College. Sixteen healthy rabbits were randomly assigned into two groups of 8each: SGB group and control group.INTERVENTIONS: A catheter was inserted close to the right stellate ganglion in each rabbit operatively. All of the rabbits received 0.5 mL formalin (80 g/L) stimulation by intraplantar injection into the right front paws. Ten minutes before stimulation, 0. 5 mL of 2.5 g/L bupivacaine was administered via the catheter in SGB group, while 0. 5 mL of normal saline was applied in the control group.MAIN OUTCOME MEASURES: Serum cortisol at 10 minutes before stimulation, 10, 60 and 120 minutes after stimulation, and β-endorphin of inflammatory tissue at 120 minutes after stimulation were measured by radioimmunological method.RESULTS: The concentration of serum cortisol increased significantly after pain stimulation at all time points compared with that before pain stimulation, and reached its peak concentration after 60 minutes in control group (462. 3±88.5) nmol/L] (P＜0.01), while the concentration did not change significantly at all time-points in SGB group( P＞0.05). There were significant differences between SGB group and control group at 10 minutes (146.3±54.8), (186.5±45.8) nmol/L, P＜0.05], 60 minutes (138.4±32.5), (462.3±88.5) nmol/L, P＜0.01] and 120 minutes (140.9±55.6), (321.4±65.3) nmol/L, P＜0.01] after stimulation,but no difference at 10 minutes before stimulation(130.2±31.7),(128.6±35.4) nmol/L, P＞0.05] . The β-endorphin concentration of inflammatory tissue was significantly higher in SGB group (1675±343) pg/g]than thatin control group (418±56) pg/g] (P＜0.01) at 120 minutes after stimulation.CONCLUSION: SGB can inhibit the upregulation of serum cortisol in rabbits with formalin stimulation, and increase β-endorphin concentration of inflammatory tissue.