硬膜外分娩镇痛的临床研究

目的 :探讨硬膜外分娩镇痛效果及其对产程、母婴状况的影响。方法 :将 0 1%布比卡因及芬太尼 5 μg/ml混合液硬膜外分娩镇痛的 30 0例产妇作为镇痛组 ,将未用任何镇痛药的 30 0例产妇作为对照组 ,比较两组的产痛程度、产程时间、分娩方式、产后出血量、羊水粪染率、新生儿窒息及缩宫素应用等。结果 :镇痛组 30 0例产妇中显效 90 33% (2 71/30 0 ) ,有效 9 6 7% (2 9/30 0 ) ,总镇痛有效率 10 0 % ;镇痛组的活跃期和第二产程时间短于对照组 ,差异有显著性意义 (P <0 0 1) ;镇痛组自然分娩率明显高于对照组 (P <0 0 5 ) ,剖宫产率则以对照组为高 (P <0 0 5 ) ;两组羊水粪染率、新生儿窒息、Apgar评分、产后出血量及缩宫素应用的比较无显著性差异 (P <0 0 5 )。结论 :硬膜外分娩镇痛是一种理想的、安全有效的分娩镇痛方法。     

Behavioral and immunohistochemical investigations of the effects of phytoestrogens on pain, analgesia, and inflammation: Gender dependency

The effects of long-term administration of the phytoestrogens (PEs) genistein (Gen) and naringenin (Nar) on nociception, imflammatory hyperalgesia, and metamizol-induced analgesia, the efficacy of PEs vs 17β-E to modulate nociception, as well as the gender dependency of PE effects, and NOS and TH (NO synthase and tyrosine hydroxylase, respectively) expression in the periaqueductal gray (PAG) were studied in gonadectomized female and male rats. The paw pressure, tail flick, and hot plate tests, incapacitance test, and plethismometry were employed for in vivo studies. For in vitro studies, immuno-or histochemical staining of NOS and TH expression in PAG were applied. Data revealed that PEs, like 17β-E, decreased nociceptive thresholds in both sexes, but more significantly in female rats. Genistein intensified carrageenan-induced exudative inflammatory reaction and modulated metamizol-induced analgesia. Long-term PE administration resulted in gender-specific alterations of NO and TH expression. The effects of PEs might be correlated with gender-specific 17β-E-like action in male and female individuals. The results suggest that, similarly to other estrogen-like compounds, PEs can play a significant role in the individualization of analgesic therapy. Neirofiziologiya/Neurophysiology, Vol. 38, No. 4, pp. 350–353, July–August, 2006.     

一足致炎大鼠双足伤害感受性的变化

大鼠一侧鹿角菜致炎足痛阈显著降低后,对侧非致炎足的痛阈出现显著降低、不变,和显著升高等变化。对侧非致炎足痛阈的这三种变化与致炎足痛阈降低幅度的大小显著相关。     

Modulation of spinal pain processing by cannabinoid receptor agonists

Manifestations of the central pain syndrome induced by applications of benzylpenicillin on the rat spinal cord were quantitatively measured after injections of endogenous and exogenous cannabinoid agonists, anandamide and WIN 55,212-2. The analgesic effects of those agents are described. Neirofiziologiya/Neurophysiology, Vol. 38, Nos. 5/6, pp. 492–494, September–December, 2006.     

不同频率的电针对大鼠神经源性痛的治疗作用

目的：探讨不同频率的电针能否减轻大鼠神经源性痛。方法：将大鼠右侧L5／L6脊神经结扎,用引起50％抬足的机械刺激阈值评价机械性痛觉超敏,用大鼠5min内从5℃冷权上的抬足次数反映冷诱发的持续性疼痛。用韩氏穴位神经刺激仪给与2Hz或100Hz电刺激。结果：①2Hz和100Hz电针均一轻痛觉超敏,2Hz起效较早。②两种频率电针均能减轻冷诱发的持续性疼痛,但2Hz持续的时间长,多次电针后2Hz的镇痛效果可持续长达48h。③针刺而不通电也能显著减轻冷诱发的持续性痛。结论：电针能减轻神经源性痛,且低频（2Hz）电针的镇痛效果优于高频（100Hz）电针。     

Diabetic neuropathy enhances voltage-activated Ca2+ channel activity and its control by M4 muscarinic receptors in primary sensory neurons

Painful neuropathy is one of the most serious complications of diabetes and remains difficult to treat. The muscarinic acetylcholine receptor (mAChR) agonists have a profound analgesic effect on painful diabetic neuropathy. Here we determined changes in T-type and high voltage-activated Ca(2+) channels (HVACCs) and their regulation by mAChRs in dorsal root ganglion (DRG) neurons in a rat model of diabetic neuropathy. The HVACC currents in large neurons, T-type currents in medium and large neurons, the percentage of small DRG neurons with T-type currents, and the Cav3.2 mRNA level were significantly increased in diabetic rats compared with those in control rats. The mAChR agonist oxotremorine-M significantly inhibited HVACCs in a greater proportion of DRG neurons with and without T-type currents in diabetic than in control rats. In contrast, oxotremorine-M had no effect on HVACCs in small and large neurons with T-type currents and in most medium neurons with T-type currents from control rats. The M(2) and M(4) antagonist himbacine abolished the effect of oxotremorine-M on HVACCs in both groups. The selective M(4) antagonist muscarinic toxin-3 caused a greater attenuation of the effect of oxotremorine-M on HVACCs in small and medium DRG neurons in diabetic than in control rats. Additionally, the mRNA and protein levels of M(4), but not M(2), in the DRG were significantly greater in diabetic than in control rats. Our findings suggest that diabetic neuropathy potentiates the activity of T-type and HVACCs in primary sensory neurons. M(4) mAChRs are up-regulated in DRG neurons and probably account for increased muscarinic analgesic effects in diabetic neuropathic pain.     

镇痛指数在全麻手术中评估镇痛程度的临床价值

目的：探讨脑电镇痛指数（PRi）评估全身麻醉手术中镇痛程度的临床价值,为临床应用提供理论依据。方法：ASAI-Ⅱ级,拟于全身麻醉下行经腹手术的病人20例。患者入手术室后持续有创监测收缩压（SBP）、舒张压（DBP）、心率（HR）,实时监测脑电双频指数（BIS）和镇痛指数（PRi）。于麻醉诱导后气管插管前,气管插管后1 min、切皮前、切皮后2 min、追加芬太尼前,追加芬太尼5 min后记录BIS、PRi、SBP、DBP、HR的变化。结果：气管插管和切皮均引起SBP、DBP、HR的显著升高（P<0.05）;追加芬太尼后SBP、DBP、HR均降低（P<0.05）。气管插管和切皮均未引起BIS的显著变化（P>0.05）;追加芬太尼后BIS有所下降（P<0.05）。气管插管和切皮均引起PRi的显著升高（P<0.05）;追加芬太尼后PRi降低（P<0.05）。气管插管和切皮均引起SBP、DBP、HR、PRi的显著升高（P<0.05）,但均未引起BIS的显著变化（P>0.05）;追加芬太尼后SBP、DBP、HR、BIS和PRi均明显降低（P<0.05）。结论：在丙泊酚联合瑞芬太尼全身麻醉手术中,PRi能够反映伤害性刺激的变化,与伤害性刺激过程一致,对全身麻醉中镇痛程度的评估有指导意义。     

中枢催产素在电针镇痛中的作用

本工作以钾离子透入法引起大鼠甩尾反应的电流强度(mA)为痛反应指标,观察了侧脑室注射催产素(OT)及抗催产素血清(AOTS)对大鼠痛阈和电针镇痛效应的影响。注射50 ngOT 后80min 内,大鼠痛阈比注药前增加20—38%。与注射生理盐水组的痛阈相比有非常明显的增高(p<0.01—0.001),侧脑室注射 OT 后电针期内,痛阈增加139—234%,与生理盐水电针组相比,有显著差异(P<0.05—0.01)。OT 的剂量在25—100ng 范围内,其增强电针镇痛效应有明显的剂量-效应关系。注射 AOTS 后,电针镇痛应明显低于注射正常兔血清(NRS)组(p<0.05—0.01)。上述结果表明,侧脑室注射 OT,既可提高痛阈又可明显地增强电针镇痛效应,而用 AOTS消除内源性 OT 的作用后,电针镇痛效应明显降低。这提示,中枢神经系统内的 OT 在电针镇痛过程中,发挥一定的作用     

糖皮质激素在慢性疼痛中的双重作用机制

糖皮质激素(glucocorticoid,GC)是下丘脑-垂体-肾上腺(hypothalamic-pituitary-adrenal,HPA)轴分泌的最终效应激素,通过与糖皮质激素受体(glucocorticoid receptors,GR)结合行使功能。研究发现,GC在慢性疼痛中表现双重作用,内源性GC作为抗炎类固醇通过募集免疫细胞、抑制激酶通路、调节神经胶质细胞在部分类型的神经病理性疼痛及炎性痛中发挥抑痛作用,但在应激情况下,GC水平异常升高参与中枢神经系统神经元的凋亡、兴奋、记忆等,通过调控不同的信号反应或微环境促进病理性疼痛。本文综述GC在慢性疼痛中的作用,了解其发挥镇痛或致痛的双重作用机制。     

电针对大鼠尾核痛兴奋,痛抑制神经元放电和甩尾反射的影响

浅麻醉ｗｉｓｔａｒ大鼠２５只,用Ｇ－６８０５型治疗仪电针刺激双侧“足三里”。以辐射热照尾部作为伤害性刺激,将痛兴奋神经元（ＰＥＮ）诱发放电频率减少,痛抑制神经元（ＰＩＮ）诱发放电频率增加和甩尾反射潜伏期（ＴＦＬ）延长作为镇痛效应,观察电针刺激“足三里”对尾核中ＰＥＮ、ＰＩＮ及ＴＦＬ的影响。结果表明,电针刺激“足三里”,尾核中ＰＥＮ、ＰＩＮ放电及ＴＦＬ均显示镇痛效应;电针对ＰＥＮ、ＰＩＮ放电及ＴＦＬ的影响高峰均出现在电针后即刻;电针前ＰＥＮ放电频率增加、ＰＩＮ放电频率减少与甩尾反射（ＴＦ）相伴行。放电变化发生在ＴＦ之前,结束在ＴＦ之后,ＰＥＮ、ＰＩＮ放电变化与ＴＦＬ呈高度正相关。镇痛作用高峰期ＰＥＮ、ＰＩＮ放电变化仍在ＴＦ前,结束在ＴＦ之后,两者呈高度正相关。提示尾核中的ＰＥＮ、ＰＩＮ是痛觉调节中枢的一部分,可能参与对ＴＦ的调节。     

压脚痛阈测定法的改进和应用

本文介绍一种改进的压脚测痛法。采用电机驱动替代用手挤压橡皮球完成升压过程;通过一个自动的电路切断结构判定抽脚反应,较目视更加客观;用读数保持电路记录压力变化,较直接读取刻度值更加准确,可靠。这些优点,业经电针和吗啡镇痛实验验证。     

Effects of melatonin and antagonists of MT1 and MT2 receptors on somatic pain induced within the fixed circadian rhythm

We studied behavioral pain-related reactions (PRRs) induced in mice by subcutaneous injections of 5% formalin within different phases of the fixed circadian illumination rhythm under conditions of administration of exogenous melatonin and of blocking of MT1 and MT2 melatonin receptors. It was demonstrated that modulation of experimentally induced somatic pain depends considerably on the phase of the preset circadian rhythm. In the norm, the duration of PRRs in the middle of the dark phase was 30% smaller than that in the middle of the light phase. Administration of exogenous melatonin in the middle of the light phase decreased the duration of episodes of noxious behavior by 43%, on average. Injections of melatonin within the dark phase resulted in no significant changes in the duration of PRRs. In the dark phase, the blockade of MT1 receptors by luzindole led to an increase in the duration of PRRs by 45%, as compared with the norm, while in the light phase we observed no significant alterations of this duration under conditions of blocking of the above-mentioned receptors. The blockade of MT2 receptors by prazocine in the middle of dark and light phases increased the durations of PRRs by 92 and 28%, respectively. Our data indicate that the analgesic effect of melatonin depends significantly on the level of this hormone in the organism; in turn, such a level is determined by the illumination conditions. The antinoxious effect of melatonin is mediated by MT receptors, in particular by MT2 receptors. Neirofiziologiya/Neurophysiology, Vol. 39, No. 3, pp. 255–259, May–June, 2007.     

The influence of women’s attachment style on the chronobiology of labour pain,analgesic consumption and pharmacological effect

Circadian variation in biological rhythms has been identified as affecting both labour pain and the pharmacological properties of analgesics. In the context of pain, there is also a growing body of evidence suggesting the importance of adult attachment. The purpose of this study was to examine whether labour pain, analgesic consumption and pharmacological effect are significantly affected by the time of day and to analyse whether this circadian variation is influenced by women’s attachment style. This prospective observational study included a sample of 81 pregnant women receiving patient-controlled epidural analgesia (PCEA). Attachment was assessed with the Adult Attachment Scale – Revised. The perceived intensity of labour pain in the early stage of labour (3?cm of cervical dilatation and before the administration of PCEA) was measured using a visual analogue scale (VAS). Pain was also indirectly assessed by measuring the consumption of anaesthetics. The latency period and the duration of effect were recorded for a chronopharmacology characterisation. Pain, as assessed with the VAS, was significantly higher in the night-time group than in the daytime group. An insecure attachment style was significantly associated with greater labour pain at 3?cm of cervical dilatation (p?<?0.001) and before the beginning of analgesia (p?<?0.001) as well as with higher analgesic consumption and lower pharmacological efficacy (p?<?0.05). The time of day was significantly associated with the pharmacological effect: the latency period was longer at night, and the duration of the pharmacological effect was longer during the daytime. The interaction between time of day and attachment style was not significant for any of the study variables. Our results provide evidence of the importance of circadian variation in studying labour pain and the pharmacological effect of labour analgesia involving epidural blockage with a PCEA regimen. Moreover, although there was no evidence that attachment style influenced the circadian variation, these data emphasise that insecure attachment patterns are a risk factor for greater labour pain and analgesic consumption, which should be considered in pain management approaches.