利鲁唑对吗啡镇痛、耐受和依赖作用的影响(英文)

目的　研究利鲁唑对阿片镇痛、耐受及躯体功能的调节。方法　采用冰醋酸扭体 ,5 5℃热板法和热辐射甩尾法观察利鲁唑对小鼠痛阈及吗啡镇痛效应的影响 ;采用小鼠急性和慢性吗啡耐受模型及小鼠吗啡依赖模型 ,观察利鲁唑对吗啡耐受和依赖的作用。结果　单独皮下注射利鲁唑 2 .5～ 10mg·kg- 1在以上 3种模型无镇痛作用 ,然而能剂量依赖性地增强吗啡镇痛效应。利鲁唑 2 .5～ 10mg·kg- 1剂量依赖性地对抗吗啡引起的急性和慢性耐受。在小鼠吗啡依赖模型中 ,利鲁唑 2 .5～ 10mg·kg- 1剂量依赖性地抑制吗啡戒断症状的产生。结论　利鲁唑自身无镇痛作用 ,但能显著增强吗啡镇痛效应 ,并能预防吗啡所引起的耐受和依赖     

胍丁胺代谢产物腐胺对吗啡镇痛、耐受和依赖的影响

目的观察腐胺对吗啡镇痛、耐受及依赖的影响,探讨腐胺治疗阿片耐受性和依赖性的潜力。方法小鼠醋酸扭体模型和55℃热板法测痛阈;吗啡恒定剂量给药制备耐受模型,55℃热板法测痛阈;吗啡递增剂量给药制备依赖模型,纳洛酮催促观察戒断症状,以胍丁胺(40 mg.kg-1,ig)为阳性对照药,腐胺灌胃给药剂量分别为10,20,40,80 mg.kg-1。结果在小鼠醋酸扭体模型中腐胺具有镇痛作用;而在小鼠55℃热板实验中,腐胺本身无镇痛作用,能较弱地增强吗啡镇痛;腐胺能够减弱吗啡耐受的形成,对已形成的吗啡耐受也有治疗作用;腐胺能够减弱吗啡躯体依赖的形成和表达。结论腐胺和胍丁胺具有相似的生物学活性,具有治疗阿片耐受和依赖的潜力。     

Y-IP5对小鼠吗啡镇痛、耐受及躯体依赖的影响

目的:评价化合物Y-IP5对小鼠吗啡镇痛、耐受及躯体依赖的影响。方法:采用55℃热板测痛模型分析Y-IP5对小鼠吗啡镇痛和耐受的影响;采用剂量递增法皮下注射吗啡5 d,建立小鼠吗啡依赖模型,评价Y-IP5对小鼠吗啡躯体依赖的影响。结果:在热板测痛模型中,Y-IP5(2.5,5,10 mg.kg-1)不能明显增强小鼠吗啡镇痛作用(P>0.05),Y-IP5(1.25,2.5,5 mg.kg-1)能明显抑制小鼠吗啡镇痛耐受的形成(P<0.05)。伴随吗啡给予Y-IP5(1.25,2.5,5 mg.kg-1)能剂量依赖性地抑制小鼠躯体依赖的形成(P<0.05);在纳洛酮催促前单次给予Y-IP5(1.25,2.5,5 mg.kg-1),不能显著抑制小鼠吗啡躯体依赖的表达(P>0.05)。结论:Y-IP5对吗啡耐受及躯体依赖的形成可能有一定的干预作用。     

The effect of chronic administration of caffeine on morphine-induced analgesia, tolerance and dependence in mice

Morphine-induced analgesia, and the development of morphine-induced tolerance and dependence was determined in mice which had drunk caffeinated water (1 mg/ml) for 14 days or in mice which had received (-)-N6-(phenylisopropyl)-adenosine (PIA) 1 mg/kg i.p. for 14 days. Analgesia was assessed by the tail flick assay. The development of dependence was assessed by determining the ED50 of naloxone to precipitate withdrawal jumping (3 h after 100 mg/kg morphine pretreatment or 72 h after s.c. implantation of a morphine 75 mg pellet) and by determining the extent of naloxone-precipitated hypothermia in morphine-implanted animals. In mice chronically administered caffeine, the ED50 for morphine-induced analgesia was significantly decreased while the naloxone ED50 for withdrawal jumping increased by 2-fold after both types of morphine pretreatment. In control animals (tap water for 14 days), doses of 1 and 10 mg/kg of naloxone caused significant hypothermia in morphine-implanted animals. Doses of naloxone up to 100 mg/kg did not cause significant hypothermia in morphine-implanted animals which had received chronic caffeine. The development of tolerance was determined by computing the morphine potency ratio for the tail flick assay (tolerant ED50/control ED50). In mice chronically administered caffeine, the potency ratio was decreased significantly in morphine-implanted animals when compared to control. Morphine-induced analgesia, tolerance and dependence was not changed significantly in animals chronically administered PIA. Neither the distribution of morphine to the brain nor the opioid receptor binding parameters for [3H]etorphine and [3H]naltrexone were altered in mice chronically administered caffeine or PIA.(ABSTRACT TRUNCATED AT 250 WORDS)     

咪唑克生对吗啡镇痛、耐受和身体依赖的影响

目的:观察咪唑克生对吗啡镇痛及吗啡所致耐受和躯体依赖的影响.方法:采用小鼠醋酸扭体实验和55℃热板实验观察咪唑克生对基础痛阈及吗啡镇痛作用的影响;采用小鼠热辐射甩尾实验和小鼠55℃热板实验观察咪唑克生对吗啡耐受形成过程的影响;采用大鼠、小鼠身体依赖模型观察咪唑克生对吗啡所致身体依赖的影响.结果:咪唑克生(3-9mg/kg)能显著降低小鼠基础痛阈,抑制吗啡镇痛;加重吗啡所致耐受;诱发大、小鼠发生戒断综合征.结论:咪唑啉受体参与痛阈形成;咪唑克生能抑制吗啡镇痛,加重吗啡所致耐受;并诱发吗啡依赖性动物发生戒断综合征.     

Effects of nandrolone on acute morphine responses,tolerance and dependence in mice

Anabolic-androgenic steroid exposure has been proposed to present a risk factor for the misuse of other drugs of abuse. We now examined whether the exposure to the anabolic-androgenic steroid, nandrolone, would affect the acute morphine responses, tolerance and dependence in rodents. For this purpose, mice received nandrolone using pre-exposure (for 14 days before morphine experiments) or co-administration (1 h before each morphine injection) procedures. Nandrolone treatments increased the acute hypothermic effects of morphine without modifying its acute antinociceptive and locomotor effects. Nandrolone also attenuated the development of tolerance to morphine antinociception in the hot plate test, but did not affect tolerance to its hypothermic effects, nor the sensitisation to morphine locomotor responses. After nandrolone pre-exposure, we observed an attenuation of morphine-induced place preference and an increase in the somatic manifestations of naloxone-precipitated morphine withdrawal. These results indicate that anabolic-androgenic steroid consumption may induce adaptations in neurobiological systems implicated in the development of morphine dependence.     

不同阿片受体在羟考酮引起小鼠高活动性和镇痛过程中的作用

目的研究μ、δ、κ三种阿片受体在羟考酮引起小鼠高活动性和镇痛过程中的作用。方法采用小动物自主活动测定和热板镇痛实验方法。结果羟考酮(1.25,2.5,5.0mg.kg-1,s.c)使小鼠的自发活动明显增加,并成明显的量效关系。非选择性阿片受体拮抗剂naloxone能剂量依赖性的降低羟考酮引起的小鼠自发活动增加。选择性μ受体拮抗剂naloxonazine对羟考酮(5.0mg.kg-1,s.c)引起的小鼠自发活动增加没有影响,而选择性δ受体拮抗剂naltrindole能剂量依赖性的降低羟考酮引起的小鼠自发活动的增加,选择性κ受体拮抗剂nor-Binltorphimine增强羟考酮引起小鼠高活动性的作用;naloxonazine和naltrindol不影响羟考酮的镇痛作用,而nor-Binltorphimine能拮抗羟考酮的镇痛作用。结论羟考酮引起小鼠自发活动增加可能是通过δ介导的,而羟考酮的镇痛作用可能是通过κ受体介导的。     

Dose-dependent effects of prolyl-leucyl-glycinamide on morphine-induced analgesia, tolerance and dependence

Prolyl-leucyl-glycinamide (PLG) at a low dose (10 ng/mouse) administered intracerebroventricularly (i.c.v.) did not affect morphine analgesia, but produced a greater increase in the ED50 of morphine-pretreated (100 mg/kg of morphine sulfate) mice as compared to control mice. PLG at doses of 10 and 100 micrograms/mouse antagonized morphine analgesia. Development of morphine tolerance was unaffected by 10 micrograms/mouse but antagonized by 100 micrograms/mouse of PLG. Development of morphine dependence was assessed by changes in body weight and temperature during naloxone-induced withdrawal. PLG (10 ng/mouse) potentiated, 10 micrograms/mouse had no effect and 100 micrograms/mouse antagonized development of morphine dependence. PLG at doses of 10 and 100 micrograms/mouse precipitated withdrawal in morphine-dependent mice. When mice were pretreated with 1.0 mg/kg naloxone i.p. 15 min before PLG, all doses of PLG had no effect on morphine analgesia, but potentiated the development of morphine tolerance and dependence. None of the doses of PLG altered whole brain levels of morphine. PLG did not alter the affinity of opioid receptors for etorphine or the maximal number of binding sites but PLG did exhibit a very weak affinity for opioid receptors. These results indicate that PLG potentiated development of morphine tolerance and dependence through a mechanism not involving opioid receptors. However, at very high doses it was a weak opioid receptor antagonist.     

Effects of dopamine, NMDA, opiate, and serotonin-related agents on acute methamphetamine-induced self-injurious behavior in mice

We examined the biochemical processes responsible for acute methamphetamine (MAP)-induced self-injurious behavior (SIB) in mice. In initial experiments, a single dose of MAP (5, 10, or 15 mg/kg, IP) or an equivalent volume of saline was administered to male BALB/c mice. Acute MAP administration dose dependently increased the incidence of SIB (p < 0.05). In further experiments, we evaluated the effects of SCH23390, sulpiride, MK-801, naloxone or 5-hydroxy-L-tryptophan (5-HTP) on the incidence of acute MAP (15 mg/kg, IP)-induced SIB. Both SCH23390 (0.5 and 1.0 mg/kg, IP) and 5-HTP (100 and 200 mg/kg, IP) reduced the incidence of MAP-induced SIB (p < 0.05). MK-801 (0.125 and 0.25 mg/kg, IP) completely blocked the SIB induced by MAP (p < 0.001). In contrast, neither sulpiride (25, 50, and 100 mg/kg, IP) nor naloxone (1, 5, and 10 mg/kg, IP) affected the incidence of MAP-induced SIB. It is concluded that dopamine D(1), NMDA, and serotonin neurotransmission may be involved in critical biochemical processes responsible for acute MAP-induced SIB.     

Pertussis toxin inhibits morphine analgesia and prevents opiate dependence

Six days after intracerebroventricular pretreatment of rats with pertussis toxin (PTX 0.5 microgram/rat) there was a marked decrease in the antinociceptive effect of morphine, regardless of the route of opioid administration (into the periaqueductal gray matter, intrathecally or intraperitoneally) or the analgesic test used (tail flick and jaw opening reflex). PTX pretreatment also partially attenuated the naloxone-precipitated withdrawal syndrome in morphine-dependent rats, significantly reducing teeth chattering, rearing and grooming. These in vivo findings indicate that G-protein-dependent mechanisms are involved in morphine analgesia and dependence. The biochemical mechanism could be related to ADP ribosylation of Gi coupled to the adenylate cyclase system, but an interaction of PTX with other G-proteins linked to different second messengers or directly to ionic channels cannot be excluded.     

Modification of morphine-induced analgesia, tolerance and dependence by bromocriptine

The effect of two doses of bromocriptine, a dopamine agonist, on morphine-induced analgesia, tolerance and dependence was investigated in mice. Bromocriptine at doses of 0.04 and 0.08 mg/kg did not affect the baseline tail flick latency of mice but potentiated the morphine analgesia. Pretreatment of mice with 5 mg/kg of sulpiride, a D-2 antagonist, not only blocked the effect of 0.08 mg/kg of bromocriptine but also antagonized the morphine analgesia. Control animals given daily injections of 10 mg/kg of morphine rapidly developed tolerance to the analgesic effect. A combined treatment of bromocriptine with morphine given daily suppressed the development of tolerance to morphine analgesia. However, development of tolerance to morphine analgesia was not significantly modified in the animals treated daily with bromocriptine (0.08 mg/kg) plus sulpiride (5 mg/kg). Acute dependence was induced by the administration of 100 mg/kg of morphine. The administration of bromocriptine 30 min before naloxone significantly decreased the ED₅₀ value for naloxone for inducing jumping in mice. Coadministration of sulpiride and bromocriptine attenuated the ability of bromocriptine to potentiate the withdrawal syndrome of morphine dependence. The results indicate that bromocriptine potentiates morphine analgesia, suppresses the development of tolerance to morphine analgesia but exacerbates opiate withdrawal signs in morphine-dependent mice. These effects of bromocriptine appear to be mediated via D-2 receptors.     

Role of sodium cromoglycate on analgesia,locomotor activity and opiate withdrawal in mice

The role of sodium cromoglycate (CRO) on analgesia, locomotor activity and morphine withdrawal in mice was studied in morphine-dependent and drugnaive mice. CRO (0.5, 1, 5, 10, 30, 50 and 100 mg/kg, SC) induces analgesia (hot plate), an effect blocked by previous administration of the opiate antagonist naloxone (1 mg/kg). Furthermore, CRO (30 mg/kg) potentiates morphine analgesia. In morphine-tolerant mice, moderate doses of CRO (0.5, 1, 5, 10 and 30 mg/kg) do not induce analgesia, which suggested the development of cross tolerance between CRO and morphine, whereas coadministration of CRO and morphine in morphine tolerant animals restored the sensitivity to morphine. Administration of CRO (10 and 30 mg/kg) induces an increase in spontaneous locomotor activity, and previous administration of naloxone (1 mg/kg) blocks this effect, whereas CRO (10 mg/kg) blocks morphine (10 mg/kg) and amphetamine (3 mg/kg)-induced hyperactivity. CRO (10, 50 and 100 mg/kg) induces a significant and dose-dependent reduction in the number of jumps (jumping up) during naloxone (1 mg/kg)-induced withdrawal in morphine-dependent mice. Finally, CRO (100 mg/kg) reduces the wet dog shake phenomenom during naloxone-induced withdrawal in morphine-dependent mice. These results suggest a possible stabilizing effect of CRO on the membranes of neurones that mediate analgesia, locomotor activity and opiate abstinence. Changes and inhibition of DA, NA and 5-HT release may also explain these effects.This work was supported by a grant from the CICYT (Program FAR 90/0543).     

Effects of agmatine on tolerance to and substance dependence on morphine in mice

目的：观察胍丁胺对吗啡所致耐受和依赖的作用．方法：分别在小鼠耐受和跳跃实验中观察胍丁胺抑制吗啡所致耐受和物质依赖的作用．结果：胍丁胺０１２５－２５ｍｇ·ｋｇ－１剂量依赖性地阻止小鼠对吗啡耐受．用吗啡预处理小鼠使吗啡镇痛ＥＤ５０（２０１,１４４－２８０ｍｇ·ｋｇ－１）与盐水组相比（６３,５１－７８ｍｇ·ｋｇ－１）增加３倍以上．用胍丁胺和吗啡共同预处理小鼠则使吗啡丧失引起耐受的能力．胍丁胺（２５－１０ｍｇ·ｋｇ－１）剂量依赖性地抑制由纳洛酮引起的吗啡依赖小鼠之戒断跳跃和体重减轻．用胍丁胺和吗啡共同处理小鼠使引起小鼠之戒断跳跃所需纳洛酮ＥＤ５０（２１４,１８４－２４ｍｇ·ｋｇ－１）较吗啡处理组（２５,２１－２８ｍｇ·ｋｇ－１）增大８倍．胍丁胺的上述作用均被咪唑克生所阻断．结论：胍丁胺通过激活咪唑啉受体而阻止小鼠对吗啡耐受和依赖．     

Morphine analgesia, tolerance and physical dependence in the adrenalectomized rat

1. Adrenalectomy reduced the median antinociceptive dose (AD50) of morphine in male Sprague-Dawley rats. The antinociceptive effect was assessed by the tail-flick method of D'Amour & Smith (1941).2. Tolerance to the antinociceptive effect of morphine developed in adrenalectomized and sham-operated rats after chronic exposure to morphine. Development of tolerance did not significantly alter the increased sensitivity of adrenalectomized rats to the antinociceptive effect of morphine.3. Adrenal weights were not increased in rats rendered physically dependent on morphine by subcutaneous implantation of a morphine pellet. Withdrawal, induced by intraperitoneal injection of naloxone hydrochloride, 4 mg/kg, or by removal of the implanted pellet, resulted in a rapid increase in adrenal weight.4. In morphine-dependent animals, the incidence of abstinence signs and body weight loss during precipitated withdrawal did not appear to be significantly influenced by adrenalectomy or by corticosterone-pretreatment.     

Differential effects of opiate agonists-antagonists on morphine-induced hyperexcitability and analgesia in mice

The effects of two opiate agonists-antagonists, butorphanol (4.0 and 8.0 mg/kg) and buprenorphine (0.1 and 1.0 mg/kg), were assessed on locomotor activity and analgesia in DBA/2 and C57BL/6 mice. Diferrent behavioral effects were evident in these strains, which might becharacterized by different reactions to the effects of opiates and by differences in endorphin distributions and opiate receptor populations. In particular, buprenorphine acted as an agonist-antagonist to morphine in both strains while a dissociation of buturphanol effects was evident, depending on the strain considered. The clinical implications of these findings are discussed.     

Evidence for the dissociation of morphine analgesia, tolerance and dependence

A single large dose of morphine produced profound analgesia accompanied by the development of tolerance and physical dependence. The tolerance developed acutely within 24 h and was further intensified, reaching a peak on the 5th day, then gradually disappeared. Partial or complete masking of morphine analgesia by naloxone inhibited the development of the acute, but could not prevent the development of the delayed, tolerance. These results suggest there are two kinds of tolerance and that the analgesic effect is separate from tolerance. Similarly, treatment with morphine produced physical dependence which was precipitated by naloxone. Unlike tolerance, dependence did not develop when morphine analgesia was completely masked by naloxone. The findings provide for the dissociation or morphine analgesia, tolerance and dependence.     

Influence of psychogenetics in opiate tolerance and abstinence in mice

1. Four different strains of mice were used to study the influence of psychogenetics in opiate tolerance and abstinence. 2. The CD1 strain seemed to be more sensitive to naloxone administration after four days of morphine implantation, because administration of the antagonist induces a number of jumps in the withdrawal phase higher than in the case of the DBA or C3H strains. 3. DBA and C3H mice elicit analgesia before the CD1 strain, whereas the C3H mice lose body weight at a faster rate than the other strains. 4. C57 bl mice died after morphine implantation (100%). 5. These findings are discussed in relation with neurochemical and receptor variations.     

胍丁胺对吗啡所致小鼠耐受和物质依赖的作用

目的 观察胍丁胺对吗啡所致耐受和依赖的作用。方法 分别在小鼠耐受和跳跃实验中观察胍丁胺抑制吗啡所致耐受和物质依赖的作用,结果：胍下胺０．１２５～２．５ｍｇ．ｋｇ＾－１剂量依赖性地阻止小鼠对吗啡耐受,用吗啡预处理小鼠使吗啡镇痛ＥＤ５０（２０．１,１４．４－２８．０ｍｇ．ｋｇ＾－１）与盐水组相比（６．３,５．１－７．８ｍｇ．ｋｇ＾－１）增加３倍以上,用胍丁胺和吗啡共同预处理小鼠则使吗啡丧失引直耐受的能