:高渗盐水用于治疗慢性疼痛;然而,缺乏有助于优化治疗方案的临床研究.我们旨在确定鞘内注射的高渗盐水的浓度,在该浓度下,效果达到峰值,以及潜在的γ-氨基丁酸(GABA)受体相关的抗伤害感受机制。
:在体重250-300g的大鼠中进行脊神经结扎(SNL;左L5和L6)以诱发神经性疼痛。实验1:鞘内导管植入后一周,60只大鼠随机分为鞘内注射0.45%,0.9%,2.5%,5%,10%,和20%的NaCl,然后在基线和30分钟后进行行为测试,2小时,1天,和1周确定产生最大镇痛的最低浓度。实验2:在确定鞘内高渗盐水的最佳浓度后,60只大鼠随机分为四组:假,未经预处理的高渗盐水,和用两种GABA受体拮抗剂之一预处理后的高渗盐水(GABAA[bicululline],或GABAB[phaclofen])。在每次治疗后第1周和第3周进行行为测试。
:浓度大于5%的高渗盐水缓解了SNL诱导的机械性异常性疼痛,并具有显著的治疗效果。同时对热痛觉过敏和冷痛觉过敏表现出部分时间和剂量依赖性的镇痛作用。然而,用GABA受体拮抗剂预处理会抑制5%NaCl的镇痛作用。
:这项研究表明,控制神经性疼痛的机械性异常性疼痛的高渗盐水的最佳浓度为5%,其镇痛作用与GABAA和GABAB受体有关。
UNASSIGNED: : Hypertonic saline is used for treating chronic pain; however, clinical studies that aid in optimizing therapeutic protocols are lacking. We aimed to determine the concentration of intrathecally injected hypertonic saline at which the effect reaches its peak as well as the underlying γ-aminobutyric acid (GABA) receptor-related antinociceptive mechanism.
UNASSIGNED: : Spinal nerve ligation (SNL; left L5 and L6) was performed to induce neuropathic pain in rats weighing 250-300 g. Experiment 1: one week after implanting the intrathecal catheter, 60 rats were assigned randomly to intrathecal injection with 0.45%, 0.9%, 2.5%, 5%, 10%, and 20% NaCl, followed by behavioral testing at baseline and after 30 minutes, 2 hours, 1 day, and 1 week to determine the minimal concentration which produced maximal analgesia. Experiment 2: after determining the optimal intrathecal hypertonic saline concentration, 60 rats were randomly divided into four groups: Sham, hypertonic saline without pretreatment, and hypertonic saline after pretreatment with one of two GABA receptor antagonists (GABAA [bicuculline], or GABAB [phaclofen]). Behavioral tests were performed at weeks 1 and 3 following each treatment.
UNASSIGNED: : Hypertonic saline at concentrations greater than 5% alleviated SNL-induced mechanical allodynia and had a significant therapeutic effect, while showing a partial time- and dose-dependent antinociceptive effect on thermal and cold hyperalgesia. However, pretreatment with GABA receptor antagonists inhibited the antinociceptive effect of 5% NaCl.
UNASSIGNED: : This study indicates that the optimal concentration of hypertonic saline for controlling mechanical allodynia in neuropathic pain is 5%, and that its analgesic effect is related to GABAA and GABAB receptors.