β-endorphin in the brain. A role in nociception

We have known the endogenous opioid peptide β-endorphin for 20 years. Surprisingly, our knowledge of the physiological role of this peptide and its receptors in modulation of pain perception is still fragmentary. Whereas most studies have tried to elucidate the physiological role of β-endorphin by reversing evoked responses by the opioid antagonist naloxone, this review focuses on quantification of release of β-endorphin in the brain as the approach to define physiological and pathophysiological roles of β-endorphin in relation to nociception. Using a lateral ventricle-cisterna magna perfusion model in the anesthetized rat, it was shown that depolarization of neurons in the arcuate nucleus of the hypothalamus, where β-endorphin is produced, was followed by release of β-endorphin to the cerebrospinal fluid compartment. Intense activation of spinal nociceptive pathways by intrathecal capsaicin injections also led to β-endorphin release. It is concluded that there may still be good reason to quantify β-endorphin in human cerebrospinal fluid to elucidate the role of β-endorphin in pain perception.     

Long QT interval syndrome with increased QT dispersion

This case report describes the anaesthetic management of a patient with sporadic-type long QT interval syndrome (LQTS), and increased QT dispersion, who presented for removal of an ovarian cyst. Beta adrenergic blockade and adequate depth of anaesthesia for successful management is emphasized. The Successful use of epidural administration of lignocaine and opioids in addition to general anaesthesia is described.     

Decreased incidence of headache after accidental dural puncture in caesarean delivery patients receiving continuous postoperative intrathecal analgesia

To examine the effects of prolonged (> 24 h) intrathecal catheterization with the use of postoperative analgesia on the incidence of post–dural puncture headache (PDPH), charts of 45 obstetric patients who had accidental dural puncture following attempts at epidural block were reviewed retrospectively. Three groups were identified: Group I (n = 15) patients had a dural puncture on the first attempt at epidural block, but successful epidural block on a repeated attempt; Group II (n=17) patients had a dural puncture with immediate conversion to continuous spinal anaesthesia with catheterization lasting only for the duration of caesarean delivery; Group III (n= 13) patients had an immediate conversion to spinal anaesthesia and received post–caesarean section continuous intrathecal patient–controlled analgesia consisting of fentanyl 5 (ig'ml^-1 with bupivacaine 0.25 mg·ml^-1 and epinephrine 2 μg·ml^-1 with catheterization lasting >24 h. No parturient in group III developed a PDPH. This was substantially lower ( P < 0.009) than the 33% incidence for group I and the 47% incidence for group II. The incidence of a PDPH did not differ between group I and II. Similarly, there was no difference between group I and II with regard to requests for a blood patch. Patients receiving continuous intrathecal analgesia had excellent pain relief, could easily ambulate and none complained of pruritus, nausea, vomiting, sensory loss or weakness. In conclusion, indwelling spinal catheterization > 24 h with continuous intrathecal analgesia following accidental dural puncture in parturients may for some patients be a suitable method for providing PDPH prophylaxis and postoperative analgesia.     

绵毛黄芪苷和苦玄参苷的中枢抑制作用

报道了绵毛黄芪苷(SK)及其同类结构苦玄参苷(PIA)给予昆明种式BLC_(57)/1小鼠50mg/kg腹腔注射能明显延长硫贲妥钠的睡眠时间,用扭体法或热板法证实同量SK或PIA静脉注射能产生明显的镇痛作用。用格斗试验证实:同量SK或PIA腹腔注射可使小鼠格斗试验次数明显减少。提示两种苷可能具有中枢镇静、镇痛和安定作用;此类中枢抑制作用说明四环三萜皂苷类具有药用价值的前景。     

小叶锦鸡儿的药理作用

小叶锦鸡儿１ｇ／ｋｇ，０．５ｇ／ｋｇ灌胃给药明显地提高小鼠热痛阈（Ｐ＜０．００１），减少酒石酸锑钾所致的小鼠扭体反应次数（Ｐ＜０．０１），对抗二甲苯所致小鼠耳壳炎症（Ｐ＜０．０１），抑制蛋白加热变性（Ｐ＜０．０１），明显地降低氯仿诱发的小鼠室颤发生率。     

THE ROLE OF P_1-PURINERGIC RECEPTORS IN THE SPINAL MECHANISMS OF ACUPUNCTURE ANALGESIA

It has been extensively proved that electro-acupuncture elicit analgesia in bothextensive areas and local region via supraspinal structures and spinal cord.The present investigationwas to study the role of P_1-purinergic receptors in the spinal mechanisms of weak electroacupuncture-induced analgesia.Leg withdrawal latency(LWL)to noxious radiant heat focused on the ankle regionwas used to assess the effects of acupuncture and that of P_1-purinergic(adenosine)receptor antago-nists,theophylline and caffeine on the electro-acupuncture(EA)analgesia.EA prolonged the LWLby 16.7%±20.3%,with an after-effect lasting about 15 min.Both theophylline and caffeineblocked the EA-induced prolongation of LWL in a dose-dependent manner at the doses of 1.6-16 mg/kg.These results suggest that P_1-purinegic receptor is involved in the spinal mechanisms of weak EAproduced analgesia in the rat.     

新法加工附子与附片抗炎镇痛作用比较研究

目的：比较新法加工附子在总生物碱高于附片13倍时，其抗炎、镇痛的效果是否有差异。方法：通过小鼠热板法、扭体法、小鼠耳廓肿胀法和大鼠足趾肿胀法进行镇痛和抗炎作用比较。结果：二者对热板法小鼠的痛阈值均无提高．均能减少酒石酸钾所致小鼠扭体次数．对二甲苯所致小鼠耳廓肿胀和角叉菜胶所致大鼠足趾肿胀具有抑制作用。但二者之间比较差异无显著性。结论：新法加工附子保存了其原有疗效，但和总生物碱无量效相关性，其中是否有新的活性成份，有待进一步研究探讨。     

可乐定透皮贴剂联合芬太尼静脉自控镇痛用于原发性高血压病人术后镇痛

目的 观察可乐定透皮贴剂联合芬太尼静脉自控镇痛(PCIA)用于原发性高血压(EH)病人术后镇痛的效果.方法 择期全麻下行腹腔镜胆囊切除术病人60例,均合并EH,依据术后镇痛方法的不同,随机均分为三组,肌注哌替啶组(P组)、芬太尼PCIA组(F组)和可乐定透皮贴剂联合芬太尼PCIA组(CF组).使用芬太尼1.0mg稀释至100ml,PCIA均采用负荷量-持续背景量-PCA量模式,背景剂量芬太尼20 μg/h,PCA追加剂量5 μg,锁定时间15 min.记录病人术后镇痛4、8、24、48 h VAS及Ramsay镇静评分,并记录不良反应和处理措施.监测入院时、术后24、48 h血浆内皮素(ET)及降钙素基因相关肽(CGRP)浓度、血糖(Glu),同时记录MAP、HR.结果 镇痛期间F、CF组VAS低于P组(P<0.01),CF组低于F组(P<0.05).Ramsay镇静评分F组高于P组(P<0.01),CF组高于F组(P<0.05),三组均无过度镇静.CF组MAP、HR术后较入院时明显降低(P<0.01),血浆ET、血浆CGRP浓度与入院时比较差异无统计学意义.术后ET、Glu浓度和MAP、HR F组低于P组,CGRP浓度高于P组(P<0.05).术后ET、Glu浓度和MAP、HR P组>F组>CF组;术后CGRP浓度:CF组>F组>P组(P<0.05).不良反应发生率三组差异无统计学意义.结论 对高血压病人,可乐定透皮贴剂增强芬太尼PCIA镇痛作用,使血流动力学更稳定.     

比较布托啡诺、芬太尼及芬太尼联合曲马多用于老年患者术后镇痛的临床效果

目的研究布托啡诺用于老年患者术后静脉镇痛的疗效及不良反应。方法60例择期行上腹部手术的老年患者,随机均分为布托啡诺组(B组)、芬太尼组(F组)及芬太尼联合曲马多组(FT组),分别接受持续静脉镇痛。记录并比较术后48h内疼痛视觉模拟评分(VAS)、Ramsay镇静评分及不良反应。结果三组术后镇痛效果VAS组内比较差异无统计学意义。但术后6hF组和B组的VAS明显低于FT组(P<0.05);术后12h,B组的VAS仍低于FT组(P<0.05)。B组术后0.5、6、12h Ramsay镇静评分明显高于F组(P<0.05)。B组恶心呕吐发生率明显低于FT组(P<0.05)。结论布托啡诺可用于老年患者术后静脉镇痛。     

HP 818: A centrally acting analgesic with neuroleptic properties

HP 818 (1-benzoyl-6-fluoro-3-(1-methyl-4-piperidinyl)-1H-indazole) exhibits the profile of a potent nonnarcotic analgesic with neuroleptic properties. HP 818 blocks the effects of chemical (phenylquinone), pressure (tail clip), and radiant heat (tail flick) painful stimuli in mice (ED₅₀ values of 0.3, 1.2, and 4.1 mg/kg s.c., respectively). This compound displays antinociceptive activity by the subcutaneous, oral, and intravenous routes of administration. It is also effective in the shock titration assay in squirrel monkeys and in a model of surgically induced pain. The rank order of potency of HP 818 and several other standard compounds in these tests for analgesia was Innovar > fentanyl > HP 818 > codeine > droperidol. In addition to its antinociceptive effects, HP 818 possesses neuroleptic properties. It is active in the climbing mouse, pole climb avoidance, and intracranial self-stimulation assays (ED₅₀ values of 1.8, 1.7, and 2.5 mg/kg i.p., respectively). Moreover, HP 818 inhibits amphetamine- and apomorphine-induced stereotypy, indicative of D₂-dopaminergic blocking properties. HP 818, unlike typical neuroleptic agents, does not induce supersensitivity to the effects of apomorphine when administered chronically in mice. In contrast to the clinical standard neuroleptanalgesic Innovar, HP 818 (1.0–3.0 mg/kg i.v.) produces no significant cardiovascular or respiratory changes in the anesthetized dog. Thus, HP 818 is potentially an effective presurgical medication due to its nonnarcotic analgesic activity and sedative neuroleptic effects, along with its lack of limiting cardiorespiratory side effects.