Tolerance and inverse tolerance to the hyperalgesic and analgesic actions,respectively, of the novel analgesic,F 13640

5-HT(1A) receptor activation by the very-high-efficacy, selective 5-HT(1A) receptor agonist F 13640 [(3-Chloro-4-fluoro-phenyl)-[4-fluoro-4-([(5-methyl-pyridin-2-ylmethyl)-amino]-methyl)piperidin-1-yl]-methanone] was recently discovered to constitute a novel central mechanism of broad-spectrum analgesia that, remarkably, grows rather than decays with chronicity. However, in rodents not exposed to nociception, F 13640 induces its analgesic effect only after having initially induced hyperalgesia. Numerical simulations implementing a signal transduction theory here show that the progressive increase in the intensity of nociceptive stimulation which F 13640 presumably mimics should eventually produce a large analgesic effect without initially causing marked pain. In vivo studies examined the effects of progressively increasing doses of F 13640 on the threshold of mechanically induced vocalization and, also, on the 5-HT syndrome in rats. The infusion of increasing (0.04-0.63 mg/rat/day) doses of F 13640 over a 5-week period induced a large analgesia preceded by a hyperalgesic effect that was small and comparable to that induced by initial exposure to a low, 0.04 mg/rat/day dose. Furthermore, increasing the dose of F 13640 induced tachyphylaxis to the 5-HT syndrome. Producing the mirror opposite of morphine's neuroadaptive actions, F 13640 causes an analgesia that becomes more powerful with chronic administration, and this at the expense of the initial hyperalgesia which it may also produce.     

The 5-HT(1A) receptor agonist F 13640 attenuates mechanical allodynia in a rat model of trigeminal neuropathic pain

It has been reported that the treatment with a tricyclic antidepressant imipramine induces an increase in the sensitivity of 5-HT(1A) receptors and a decrease in the sensitivity of 5-HT(4) receptors in the rat hippocampus. 5-HT(1A) receptor agonists and neuroleptics also affect 5-HT(1A) receptors in different brain areas; therefore, it was of interest to compare their effects on hippocampal 5-HT receptors with the influence of the well-established antidepressant imipramine. We studied the effects of repeated treatment with imipramine, the 5-HT(1A) receptor agonists 8-hydroxy-2(di-n-propylamino)tetralin (8-OH-DPAT) and buspirone, and the neuroleptics haloperidol and clozapine on the sensitivity of rat hippocampal CA1 neurons to 5-HT(1A)- and 5-HT(4) receptor activation. Imipramine was administered for 21 days (10 mg/kg p.o., twice daily), 8-OH-DPAT for 7 days (1 mg/kg s.c., twice daily) and buspirone for 21 days (5 mg/kg s.c., twice daily). The rats received haloperidol (1 mg/kg) and clozapine (30 mg/kg) for 6 weeks in drinking water. Hippocampal slices were prepared 2 days after the last treatment with imipramine, 8-OH-DPAT or buspirone, and 5 days after the last treatment with the neuroleptics. Using an extracellular in vitro recording, we studied changes in the amplitude of stimulation-evoked population spikes, induced by 5-HT, 8-OH-DPAT and the 5-HT(4) receptor agonist zacopride. Activation of 5-HT(1A) receptors decreased, while activation of 5-HT(4) receptors increased the amplitude of population spikes. Imipramine significantly enhanced the inhibitory effects of 5-HT and 8-OH-DPAT, and attenuated the excitatory effect of zacopride. No other treatment used in the present study changed the sensitivity of hippocampal CA1 neurons to 5-HT(1A) and 5-HT(4) receptors activation. These findings indicate that adaptive changes in the sensitivity of hippocampal neurons to 5-HT(1A) and 5-HT(4) receptors agonists are specific to imipramine and may thus-at least partly-mediate its effects.     

Inhibition of fatty acid amide hydrolase produces PPAR-alpha-mediated analgesia in a rat model of inflammatory pain

Background and purpose:

We have previously demonstrated antinociceptive effects of fatty acid amide hydrolase (FAAH) inhibition that were accompanied by increases in the levels of endocannabinoids (ECs) in the hind paw. Here, the effects of the FAAH inhibitor URB597 (3′-carbamoyl-biphenyl-3-yl-cyclohexylcarbamate) on responses of spinal neurons were studied.

Experimental approach:

Extracellular single-unit recordings of dorsal horn neurons were made in anaesthetized rats with hind paw inflammation induced by λ-carrageenan. Effects of intraplantar pre-administration of URB597, or vehicle, on carrageenan-evoked expansion of peripheral receptive fields of spinal neurons and mechanically evoked responses of neurons were studied. The cannabinoid receptor type 1 (CB₁) antagonist AM251 (N-(piperidin-1-yl)-5-(4-iodophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide) and the peroxisome proliferator-activated receptor (PPAR)-α antagonist GW6471 ([(2S)-2-[[(1Z)-1-methyl-3-oxo-3-[4-(trifluoromethyl)phenyl]-1-propenyl]amino]-3-[4-[2-(5-methyl-2-phenyl-4-oxa zolyl)ethoxy]phenyl]propyl]-carbamic acid ethyl ester) were used to investigate the roles of these receptors in mediating the effects of URB597.

Key results:

URB597 (25 μg in 50 μL) pretreatment significantly inhibited carrageenan-evoked receptive field expansion and this was significantly reversed by co-administration of the PPAR-α antagonist but not the CB₁ antagonist. Pretreatment with the PPAR-α receptor agonist WY14643 ([[4-chloro-6-[(2,3-dimethylphenyl)amino]-2-pyrimidinyl]thio]acetic acid) also significantly inhibited receptive field expansion. URB597 (25 or 100 μg in 50 μL) had no significant effect on mechanically evoked responses of spinal neurons.

Conclusions and implications:

URB597 inhibited receptive field expansions but not mechanically evoked responses of spinal neurons in rats with hind paw inflammation. These effects were blocked by PPAR-α receptor antagonism. These data support the contention that URB597 exerts its antinociceptive effects by indirect inhibition of sensitization of neuronal responses at least partly through PPAR-α activation due to enhanced EC levels.     

Profound,non-opioid analgesia produced by the high-efficacy 5-HT(1A) agonist F 13640 in the formalin model of tonic nociceptive pain

Previously, we have reported that in rat models of chronic pain, in particular, the very-high-efficacy 5-HT(1A) agonist F 13640 induces unprecedented pain relief by novel neuroadaptative mechanisms that involve inverse tolerance and cooperation with nociceptive stimulation in producing analgesia. The present studies detailed the actions of F 13640 and other compounds in the formalin model of tonic nociceptive pain. Intraperitoneal injection of F 13640 (0.01-2.5 mg/kg; t -15 min) caused a dose-dependent and complete inhibition of the paw elevation and paw licking that occurred both early (0-5 min) and late (22.5-27.5 min) after the intraplantar injection of diluted formaldehyde (2.5%) in the rat. The extent to which F 13640 and other 5-HT(1A) receptor ligands inhibited these pain behaviors correlated (p < 0.05) with the extent to which they activated 5-HT(1A) receptors. Under similar conditions, some inhibitory effects were also observed with various agents that are known to produce analgesia by different peripheral and/or central mechanisms (e.g., opioids, NA/5-HT reuptake inhibitors, COX-2 inhibitors and other nonsteroidal anti-inflammatory drugs, gabapentin, and ABT-594). However, with the possible exception of morphine, the effects of all of these agents at nontoxic doses were lower than those of F 13640, in particular in inhibition of early paw elevation. The 5-HT(1A) antagonist WAY 100635, but not naloxone, antagonized the actions of F 13640. These results help to establish large-magnitude 5-HT(1A) receptor activation as a new molecular mechanism of profound, central analgesia and suggest that F 13640 may be particularly effective against pain arising from severe tonic nociceptive stimulation.     

Effects of the high-efficacy 5-HT1A receptor agonist, F 13640 in the formalin pain model: a c-Fos study

We studied the effects of the high-efficacy 5-hydroxytryptamine1A (5-HT1A) receptor agonist, F 13640 on both formalin-induced spinal cord c-Fos protein expression and pain behaviours in the rat. Replicating earlier data, F 13640 (0.63 mg/kg, i.p.; t(-15 min)) completely inhibited the elevation and licking of the formalin-injected paw. In the same animals, and in spite of the agent as in earlier data increasing the number of c-Fos labelled nuclei when it was administered alone, F 13640 markedly reduced the number of formalin-induced c-Fos labelled nuclei. This was found in both the superficial (I-II) and deep (V-VI) dorsal horn laminae (2 h post-injection: 72+/-2% and 92+/-1% of reduction, respectively; P<0.001 in either case), spinal areas that contain neurons responsive to nociceptive stimulation. Co-operation occurred so that after the co-administration of F 13640 and formalin, c-Fos expression was inferior to that induced when either stimulation was administered alone. The data provide initial evidence for the agent's inhibitory effects on noxiously evoked c-Fos expression. The results indicate that co-operation between 5-HT1A receptor activation and nociceptive stimulation powerfully inhibits responses to severe, tonic nociception.     

杨梅黄酮对炎性痛大鼠的外周镇痛作用

目的研究杨梅黄酮对炎性痛大鼠的外周镇痛作用及机制。方法采用大鼠左侧后肢足底中心皮下注射完全弗氏佐剂(complete Freund's adjuvant,CFA)建立慢性炎性痛模型。检测给予杨梅黄酮前后大鼠热缩足反射潜伏期(thermal withdrawal latency,TWL)的改变。电生理学方法分析杨梅黄酮对背根节神经元放电频率及电压依赖性钾电流的影响。结果大鼠左侧足底皮下注射CFA致炎后,TWL明显降低(P<0.05),腹腔注射50、500 mg·kg-1杨梅黄酮使CFA组大鼠TWL明显升高(P<0.05),电流钳记录显示杨梅黄酮抑制背根节小神经元的放电频率(P<0.01),且该抑制作用是通过增加钙依赖性钾通道电流(P<0.05)产生的。结论杨梅黄酮通过增加背根节神经元钙依赖性钾电流,抑制神经元兴奋性而发挥外周镇痛作用。     

预先鞘内给予新斯的明对切口疼痛大鼠的影响

目的探讨预先鞘内给予新斯的明对切口疼痛大鼠行为学的影响。方法①采用序贯法测定预先鞘内给予新斯的明对切口疼痛大鼠镇痛作用的ED50值;②预先鞘内给予新斯的明对切口疼痛大鼠痛行为学的影响;③运用免疫组化技术观察新斯的明对脊髓背角c-fos基因表达的影响。结果①预先鞘内给予新斯的明对切口疼痛大鼠镇痛作用的ED50值为8.36μg,95%可信区间为6.68～10.70μg;②手术组大鼠累积疼痛评分明显高于F组,预先IT新斯的明可明显降低术后疼痛引起的累积疼痛评分;③与S组相比,新斯的明ED50量明显抑制c-fos蛋白的表达,作用主要产生在Ⅰ～Ⅱ层、Ⅴ～Ⅵ层,以Ⅰ～Ⅱ层分布最多。结论①预先新斯的明5～15μg鞘内应用可产生剂量依赖性的抗伤害作用;②预先鞘内注射新斯的明的抗伤害作用与抑制c-fos蛋白的表达有关。     

The analgesic efficacy of suprofen in periodontal and oral surgical pain

Suprofen is a new, orally effective nonsteroidal antiinflammatory analgesic of the propionic acid chemical class. Three separate single-dose studies were performed to evaluate the efficacy of suprofen in acute pain associated with periodontal surgery and removal of impacted third molars. Study medications were: A--suprofen 200 mg, codeine 60 mg, propoxyphene HCl 65 mg, and placebo; B--suprofen 400 mg and 200 mg, aspirin 650 mg, and placebo; C--suprofen 400 mg and 200 mg, aspirin 650 mg with codeine 60 mg, aspirin 650 mg alone, and placebo. Analgesic and side effect data were collected over a 6-hour period after patients medicated for moderate to severe pain. All studies were randomized, double-blinded, and parallel-group in design. Suprofen was significantly more effective than codeine 60 mg, propoxyphene HCl 65 mg, and aspirin 650 mg. Suprofen 400 mg appeared to be clinically more effective than the aspirin-codeine combination and the difference was statistically significant for most of the analgesic variables. Of the 224 patients who received suprofen in the 3 studies, 16 reported drowsiness and 1 reported constipation.     

Patient-controlled analgesia in the management of postoperative pain

Patient-controlled analgesia (PCA) is a delivery system with which patients self-administer predetermined doses of analgesic medication to relieve their pain. Since its introduction in the early 1980s, the daily management of postoperative pain has been extensively optimised. The use of PCA in hospitals has been increasing because of its proven advantages over conventional intramuscular injections. These include improved pain relief, greater patient satisfaction, less sedation and fewer postoperative complications. All PCA modes contain the following variables: initial loading dose, demand dose, lockout interval, background infusion rate and 1-hour or 4-hour limits. Morphine is the most studied and most commonly used intravenous drug for PCA. In spite of the fact that it is the 'first choice' for PCA, other opioids have been successfully used for this option. The most observed adverse effects of opioid-based PCA are nausea and vomiting, pruritis, respiratory depression, sedation, confusion and urinary retention. Although intravenous PCA is the most studied route of PCA, alternative routes have extensively been described in the literature. PCA by means of peridural catheters and peripheral nerve catheters are the most studied. Recently, transdermal PCA has been described. The use of peripheral or neuraxial nerve blocks is recommended to avoid the so called opioid tolerance observed with the intravenous administration of opioids. Numerous studies have shown the superiority of epidural PCA to intravenous PCA. The beneficial postoperative effects of epidural analgesia are more apparent for high-risk patients or those undergoing higher risk procedures. PCA with peripheral nerve catheters results in increased postoperative analgesia and satisfaction for surgery on upper and lower extremities. Serious complications occur rarely with these catheters. With the introduction of an Acute Pain Service, management of postoperative pain can be improved. This will also help to minimise adverse effects related to PCA and to avoid lethal mishaps.     

Different mechanisms underlie the analgesic actions of paracetamol and dipyrone in a rat model of inflammatory pain

BACKGROUND AND PURPOSE: The analgesics, paracetamol and dipyrone are weak inhibitors of the cyclooxygenase isoforms 1 or 2 (COX-1, COX-2) but more potent on COX-3. Both are also weak anti-inflammatory agents, relative to their analgesic and antipyretic activities. In a model of inflammatory pain mediated by prostaglandins, both compounds were analgesic. We have analysed this shared effect further in order to elucidate the underlying mechanisms.EXPERIMENTAL APPROACH: Inflammation was induced in one hind paw of rats by intraplantar injection of 250 microg lambda-carrageenan (CG) and the contralateral paw injected with saline. Nociceptive thresholds to mechanical stimulation were measured immediately before and for 6 h after, injection of CG. The analgesics were s.c. or locally (intraplantar) injected either 30 min before or 2 h after CG. In some groups, naltrexone was injected (s.c. or intraplantar), 1 h before CG. KEY RESULTS: Pretreatment with paracetamol or dipyrone (60-360 mg kg(-1)) reversed hyperalgesia induced by CG and increased nociceptive threshold in the inflamed paw above the basal level (hypoalgesia). Paracetamol, but not dipyrone, also raised nociceptive thresholds in the non-inflamed paw. Subcutaneous, but not local, administration of naltrexone, a specific opioid antagonist, reversed the hypoalgesia induced by paracetamol, but similar naltrexone treatment had no effect on dipyrone-induced analgesia.CONCLUSIONS AND IMPLICATIONS: Although both paracetamol and dipyrone are inhibitors of COX isoforms and thus of prostaglandin biosynthesis and were analgesic in our model, their analgesic actions were functionally and mechanistically different. Satisfactory mechanisms of action for these analgesics still remain to be established.     

The analgesic efficacy of diclofenac dispersible and ibuprofen in postoperative pain after dental extraction

Summary We have compared single oral doses of drinkable diclofenac dispersible (50 mg) with ibuprofen (400 mg) and placebo in a randomized, double-blind, parallel-group trial in 127 adults complaining of at least moderately severe pain after removal of an impacted third molar. Within 40 min both diclofenac and ibuprofen produced significant pain relief that persisted for 6 h. There were no differences between diclofenac and ibuprofen in analgesic efficacy.     

The analgesic effect of intravenous indoprofen and lysine acetylsalicylate in patients with postoperative pain

Indoprofen, as isoindolinyl derivative, was evaluated as a postoperative analgesic in a randomized double-blind, between-patients study on 40 men with postgastrectomy pain. Single intravenous doses of 100 and 300 mg indoprofen and 0.5 and 1.5 Gm lysine acetylsalicylate (ASA) were compared in a four-point assay. The method of evaluation relied on subjective appraisal of pain relief by the patient for 6 hours after medication. The results demonstrate the analgesic efficacy of indoprofen in patients with severe postoperative pain, a dose-dependent effect, and a 13-to-16 potency ratio to ASA as judged from total pain relief.     

Pharmacological profiles of the novel analgesic M58996 in rat models of persistent and neuropathic pain

We investigated the effects of 4-(N-{1-[2-(4-cyanophenyl)ethyl]-4-hydroxypiperidin-4-ylmethyl}-N-methylamino)benzoic acid monohydrochloride (M58996), a novel analgesic, on persistent and neuropathic pain in rats. In the formalin test, oral M58996 (0.3 - 10 mg/kg) reduced nociceptive behaviors only in the late phase. In the neuropathic pain model, oral M58996 (1 - 10 mg/kg) attenuated mechanical allodynia and heat hyperalgesia in the nerve-injured paw without affecting normal responses of the uninjured paw. High doses (10 - 100 mg/kg) of oral M58996 did not influence normal motor function. Thus, M58996 had a wide dose range showing antinociceptive, antiallodynic, and antihyperalgesic effects without motor dysfunction. In addition, we studied the possible mechanisms involved in the M58996-induced antinociception. The antinociceptive effect of M58996 was reversed by intrathecal pertussis toxin, an inhibitor of the inhibitory- and other-GTP-binding protein (G(i/o) protein), but not by subcutaneous naloxone, an opioid-receptor antagonist. This effect was also reversed by intracerebroventricular or intrathecal tropisetron, a 5-hydroxytryptamine(3) (5-HT(3))-receptor antagonist, and intraperitoneal bicuculline, a gamma-aminobutyric acid(A) (GABA(A))-receptor antagonist. These results suggest that M58996 produces its antinociceptive effect by a pertussis toxin-sensitive G protein mechanism. In addition, the GABA released by the activation of supraspinal and/or spinal 5-HT(3) receptors is likely to contribute to the M58996-induced antinociception.     

In the formalin model of tonic nociceptive pain, 8-OH-DPAT produces 5-HT1A receptor-mediated, behaviorally specific analgesia

The experiments examined antinociceptive and intrinsic behavioral effects induced by the prototypical 5-HT1A receptor agonist 8-OH-DPAT (8-hydroxy-2-[di-n-propylamino] tetralin) in rats. 8-OH-DPAT (0.01-2.5 mg/kg, subcutaneous (s.c.)) reduced both the paw licking and paw elevation induced by (2.5%) formalin injection into the plantar surface of the right hindpaw; it also produced forepaw treading. All of these effects were completely blocked by pretreatment with WAY 100635 (N-(2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl)-N-(2-pyridinyl) cyclohexanecarboxamide trihydrochloride) (0.16 mg/kg, s.c.); prazosin (0.63 mg/kg, s.c.) inhibited forepaw treading, but not 8-OH-DPAT's action on paw elevation and paw licking. Repeated injection of 8-OH-DPAT (0.63 mg/kg, s.c.) twice daily for 4 days, markedly reduced 8-OH-DPAT's ability to produce forepaw treading, but exerted only little and inconsistent effects on its paw licking and paw elevation-inhibiting action. The data indicate that 8-OH-DPAT exerts an analgesic action in the formalin model of tonic nociceptive pain; this action is mediated by 5-HT(1A) receptors, and is not confounded by the productive sign (i.e., forepaw treading) of the 5-HT syndrome which 8-OH-DPAT also induces.     

Tonazocine mesylate in postoperative pain patients: a double-blind placebo controlled analgesic study

One hundred-fifty post-operative adult patients with moderate to severe pain were enrolled into this analgesic efficacy study comparing single doses of tonazocine mesylate, a new mixed agonist-antagonist opioid analgesic, with morphine. The patients were randomly assigned to five treatment groups: tonazocine mesylate 2, 4, 8 mg; morphine sulfate 10 mg and a placebo group. The results showed mean total pain relief scores for tonazocine 4 mg were nearly identical with that of morphine sulfate 10 mg while 8 mg of tonazocine were superior to 10 mg of morphine. All the active medication groups were superior to the placebo group (P less than 0.02) for both pain intensity and pain relief. Relative potency determined by the dose response indicates that 3.2 mg of tonazocine is equivalent to 10 mg of morphine. Drowsiness was the main adverse reaction seen in all active treatment groups. Tonazocine mesylate appears to be a potent analgesic with promising clinical usefulness and warrants further study.     

Patient-controlled analgesia with nalbuphine,a new narcotic agonist-antagonist,for the treatment of postoperative pain

Summary Patient-controlled analgesia (PCA, intravenous self-application of narcotics) has been studied during the early postoperative period in 40 ASA I–III patients recovering from elective major and minor surgery (20 abdominal and 20 orthopaedic operations). Doses of 3.7 mg of the new agonist-antagonist opiod analgesic nalbuphine were available on demand, whenever the patients felt that pain relief was necessary, delivered by a microprocessor-controlled injection pump (On-Demand Analgesia Computer, ODAC) in response to use of a patient-controlled manual switch. The maximum dose/h was set at 28.2 mg, with a refractory time of 1 minute between successful demands. A continuous nalbuphine infusion (0.44 mg·h^–1) was administered in addition in order to prevent obstruction of the catheter.The duration of the PCA period was 17.9 (0.4–28.0) h (median, range). During that time, 13.3 (1–45) demands per patient were recorded, resulting in median individual nalbuphine consumptions of 51.3 (8.1–1050.5) µg·kg^–1·h^–1. Self-administration was characterized by considerable intra- and interindividual variability. Following abdominal surgery significantly more nalbuphine was needed compared to orthopaedic patients, but it resulted in poorer pain relief. There were no statistically significant differences in drug requirements or pain scores between the sexes.Overall efficacy and patient acceptance proved to be good. When compared with previous conventional postoperative analgesia, the effectiveness of PCA was judged superior by about 57% of patients. Side effects (nausea, sweating) occured in about 10% of patients but were usually of minor intensity. No serious circulatory or respiratory problems were observed during the period of PCA.Patient-controlled analgesia is a promising technique for the treatment of acute pain and for clinical pain research.     

Sensitivity of functional targeted neuropeptide evaluation in testing pregabalin analgesic efficacy in a rat model of osteoarthritis pain

The monosodium iodoacetate (MIA)‐induced joint degeneration in rats is the most used animal model to screen analgesic drugs to alleviate osteoarthritis (OA) pain. This study aimed to evaluate the analgesic efficacy of pregabalin (PGB) in an MIA‐induced OA model in rodents by using functional and neuroproteomic pain assessment methods. Treatment group included PGB in curative intent over 9 days compared to gold standard therapy (positive controls) and placebo (negative control). Functional assessments of pain (quantitative sensory testing and operant test) were performed concomitantly with spinal neuropeptides quantification. At day 21 post‐OA induction, PGB in MIA rats reduced tactile allodynia (P = 0.028) and improved the place escape/avoidance behaviour (P = 0.04) compared to values recorded at last time‐point before initiating analgesic therapy. All spinal neuropeptide concentrations, such as substance P, calcitonin gene‐related peptide, bradykinin and somatostatin, came back to normal (non‐affected) rat values, compared to their increase observed in MIA rats receiving the placebo (P < 0.0001). Initiated 13 days after chemical OA induction, repeated medication with PGB provided analgesia according to quantitative sensory testing, operant test and targeted neuropeptides pain assessment methods. This report highlights the interest of using reliable and sensitive methods like targeted neuropeptide quantification to detect the analgesic effects of a test article with concomitant functional assessments of pain when studying OA pain components.     

氯诺昔康对腹腔镜胆囊切除术超前镇痛的临床观察

目的：研究氯诺昔康超前镇痛对腹腔镜胆囊切除术（LC）术后镇痛、阿片类药物使用以及C反应蛋白（CRP）的影响。方法：24例LC患者，随机分为2组。对照组12例，术毕注射氯诺昔康8mg；超前镇痛组12例，麻醉诱导前15min注射氯诺昔康8mg。所有患者在术毕拔除气管导管后完全清醒时（T1）、其后1h（T2）、2h（T3）、4h（T4）进行视觉模拟评分（VAS）并检测血浆CRP含量。结果：超前镇痛组VAS值在T1、T2时间点明显低于对照组（P〈0．01）；两组患者CRP值在术前差异无显著性（P〉0．05），随着手术、麻醉的创伤，术毕两组患者CRP值与术前相比均有明显升高（P〈0．01），超前镇痛组CRP值在T1、T2时间比对照组升高更为缓慢（P〈0．01）。结论：氯诺昔康抗中枢敏感化所致超前镇痛作用可明显改善患者疼痛状态，降低应激水平。