一种新的阿片受点不可逆激动剂7α-二(β-氯乙基)胺甲基-6,14-乙烯撑基四氢奥利文的药理研究

α-CAM是一新的阿片受点不可逆激动剂,在离体组织(GPI,MVD,RVD和RbVD)及大鼠脑P_2膜制备上均表现不可逆作用。对小鼠镇痛(icv)ED_(50)为0.12 nmol/鼠,镇痛作用可持续2～3 d,是迄今所知镇痛时间最长的化合物。一次注射(icv)即可使小鼠成瘾,可作为研究成瘾机理的工具药。     

1,6-二(4-苯乙基-1-甲基-1-哌嗪基)己烷二溴化物镇痛作用及机制探讨

目的　研究哌嗪类新化合物1,6-二( 4-苯乙基1-甲基-1-哌嗪基)己烷二溴化物(97-9-G4)的镇痛作用及机制。方法　扭体法、热板法研究镇痛活性;联合给药观察纳洛酮、利血平、阿托品、CaCl₂和EDTA等对97-9G4镇痛作用的影响;并测定97-9-G4对小鼠体内PGE₂的影响。结果　sc 97-9-G4 5mg/kg即可有效抑制小鼠扭体反应(P<0.05) ;sc 40mg/kg和icv 2.5μg/kg均可明显延长热板实验的舔足阈(P<0.05) ;纳洛酮、CaCl₂和EDTA均可拮抗、减弱或加强其镇痛作用;利血平、阿托品对97-9-G4的镇痛作用影响不明显。结论　97-9-G4具有明显的镇痛活性,其镇痛作用与阿片受体及体内Ca²⁺等因素有一定关系。     

2-乙酰氧基-5-乙酰氨基苯甲酸的合成及镇痛抗炎作用

目的　合成2-乙酰氧基-5-乙酰氨基苯甲酸并进行镇痛、抗炎作用的初步研究。方法　以水杨酸和苯胺为原料,经重氮、偶合、还原及酰化合成目标化合物,化学结构经元素分析、IR和¹H-NMR确定;采用小鼠醋酸扭体、耳部肿胀法研究镇痛和抗炎作用。结果　目标化合物的熔点为170～173℃,中和法测含量99.2% ,收率42.7% (以水杨酸计)。小鼠灌胃后抑制醋酸所致疼痛的ED₅₀为1.2mmol/kg ,抑制二甲苯所致耳廓炎症的ED₅₀为2 .3mmol/kg ,LD₅₀为2598mg/kg。结论　2-乙酰氧基-5-乙酰氨基苯甲酸合成简单,收率稳定,具有比阿司匹林和对乙酰氨基酚更强的镇痛和抗炎作用。     

可乐定镇痛与中枢Ca2+的关系

用大鼠甩尾法和放射配基结合实验,探讨了可乐定镇痛与中枢Ca²⁺的关系。CaCl₂(1μmol/rat,icv)和EGTA(0.2μmol/rat,icv)分别拮抗和增强可乐定(1mg/kg,sc)的镇痛。戊脉安(0.1μmol/rat,icy)对可乐定(1 mg/kg,sc)镇痛无明显影响,但可部分翻转CaCl₂对可乐定镇痛的拮抗。CaCl₂(1×10^-3mol)对[³H]-可乐定结合无明显抑制。结果表明可乐定镇痛与脑室周围组织中Ca²⁺浓度变化密切相关,Ca²⁺至少部分需经对戊脉安敏感的钙通道进入细胞内方可拮抗可乐定镇痛。推沦:可乐定镇痛与神经元内Ca²⁺有关。     

具有柔性亲电侧链的蒂巴因和奥利文衍生物的合成和生物活性

本文报道了三个新的阿片受体亲和标记配基的合成和初步药理实验的结果,其中化合物7α-双(2-氯乙基)胺基甲基-6,14-内亚乙烯基-四氢奥利文(3),简称α-CMO,在豚鼠回肠纵行肌(GPT),小鼠输精管(MVD)及大鼠脑(去小脑)P₂膜制品中均为阿片受体不可逆结合的激动剂。镇痛试验表明它的活性为吗啡的18倍,镇痛作用持续时间达二天之久。     

去甲肾上腺素能系统对埃必定镇痛作用的影响

在大鼠电刺激甩尾测痛模型上,sc或icv埃必定(ipalbidine,Ipa)均具有剂量依赖性的镇痛作用,而脊髓蛛网膜下腔注射Ipa人产生镇痛作用;预先给予利血平可以取消scIpa的镇痛作用,这一作用可被icv补充NE所翻转;电解损毁大鼠叹侧蓝斑,ip二乙基二硫代氨基甲酸钠200mg·kg^-1,酚妥拉明ip10mg·kg^-1或icv150μg和sc哌唑嗪5mg·kg^-1均能使Ipa的镇痛作用明显减弱或消失,而sc育亨宾5mg·kg^-1和ip普萘洛尔10mg·kg^-1对Ipa的镇痛作用无明显影响。上述结果提示Ipa在中枢有镇痛作用,其部位主要在脊髓以上的神经结构,Ipa的镇痛作用可能与去甲肾上腺素能系统的a₁受体有关,而与a₂和β受体无明显关系。     

3-甲基芬太尼立体异构体的合成、绝对构型和镇痛活性

报道3-甲基芬太尼(2)四个光学异构体的合成及其绝对构型的确定,并测定了各异构体的镇痛活性(小鼠,ip,热板法)。结果表明,cis-(+)-(3R,4S)-2的镇痛作用最强,ED₅₀0.00767 mg/kg,镇痛效能是吗啡的2600倍,比其对映体cis-(-)-(3S,4R)-2以及混旋的cis-(±)-2分别强119和1.5倍;trans-(+)-(3S,4S)-2的镇痛效能是吗啡的450倍、trans-(-)-(3R,4R)-2的4倍。     

3-[p-ω-取代氨基烃氧基)-苯甲酰]-吲哚衍生物的合成

本文根据某些吲哚化合物具有抗生育活性,结合多数非甾体抗生育化合物联有碱性醚链的结构特征,设计并合成了以吲哚为母核的四种类型化合物(Ⅰ_1～7,Ⅱ_1～7,Ⅲ_1～7,Ⅳ₁)22个,并验证了三个熔点与文献报道不符的关键中间体。对小白鼠的初步药理试验表明:所合成的化合物均无抗着床作用;Ⅱ₁,Ⅱ₂,Ⅱ₄和Ⅱ₅有明显的镇痛作用;Ⅲ₂和Ⅲ₃则有较强的抗电休克作用。     

9-(4-乙氧羰基苯氧基)-6,7-二甲氧基-1,2,3,4-四氢吖啶盐酸盐抑制自由基诱发鼠皮层神经元毒性及脑缺血损伤

目的考察9-(4-乙氧羰基苯氧基)-6,7-二甲氧基-1,2,3,4-四氢吖啶盐酸盐(EDT)对自由基致原代培养大鼠皮层神经毒及小鼠脑缺血损伤的影响。方法原代培养的鼠皮层神经细胞,用H₂O₂致自由基损伤模型,测定细胞内丙二醛(MDA)及超氧化物歧化酶(SOD)活性。结扎单侧颈总动脉及迷走神经造成小鼠慢性脑缺血模型,用跳台法研究EDT对记忆障碍的影响。同时,检测了大脑皮层形态学变化,脑匀浆内MDA,NO含量及SOD活力。结果在原代培养神经元,0.01～3 μmol·L^-1 EDT浓度依赖地抑制H₂O₂诱发的MDA生成及SOD活力降低。在小鼠脑缺血模型,EDT 2.5,5和10 mg·kg^-1 ig 5 d可显著改善脑缺血小鼠的记忆障碍,对抗脑内NO释放及MDA生成,增加SOD活力。结论EDT能有效对抗自由基诱发的神经元毒性及脑缺血损伤。     

1,3-二甲基-4-酰基-5-吡唑酮二烃基锡抗癌配合物与单核苷酸作用的研究

目的研究1,3-二甲基-4-乙酰基-5-吡唑酮(HL₁)的二烃基锡抗癌配合物在近生理条件下与单核苷酸和DNA的作用机制。方法以高分辨核磁共振研究有机锡化合物在不同时间、不同条件下与核苷酸的作用方式并用UV法进一步研究有机锡化合物与DNA的作用。 结果(L₁)₂SnEt₂与AMP作用时可引起AMP碱基上H(8),H(2)和³¹P峰化学位移值显著变化并可引起DNA增色效应;(L₁)₂SnMe₂与AMP作用时只引起AMP的³¹P化学位移值的显著变化,未观察到AMP的H(8)和H(2)化学位移值的明显改变,(L₁)₂SnMe₂与DNA的作用可导致DNA的减色效应;(L₁)₂SnEt₂和(L₁)₂SnMe₂在与dCMP和dGMP作用时只引起dCMP和dGMP的³¹P的化学位移数值的明显变化。结论 3-二甲基-4-乙酰基-5-吡唑酮的二乙基锡配合物(L₁)₂SnEt₂可与AMP的碱基N₁和磷酸根氧原子螯合并可能会破坏DNA的双股螺旋结构;而二甲基锡配合物(L₁)₂SnMe₂易与单核苷酸的磷酸氧结合,难以与单核苷酸的碱基氮原子稳定结合且只引起DNA双股螺旋的收缩。     

In vitro characterization of J-113397, a non-peptide nociceptin/orphanin FQ receptor antagonist

The lack of availability of a selective, highly potent, competitive antagonist for the nociceptin receptor (OP4) devoid of residual agonistic activity has hampered studies in this area. We report here the in vitro pharmacological properties of the novel non-peptide OP4 antagonist, J-113397, which was recently discovered by Banyu Pharmaceutical investigators. The compound was synthesized as a racemic mixture in our laboratories. J-113397 was shown to antagonize (pA2 7.52) the nociceptin-induced inhibition of cAMP formation in cells expressing the recombinant human OP4 receptor (CHOhOP4) and to displace [125I]Tyr14nociceptin from CHOhOP4 membranes with a pKi of 8.56. It also competitively antagonized the contractile actions of nociceptin in the mouse colon (pA2 8.07) and the inhibitory effect of nociceptin in electrically stimulated preparations such as the mouse vas deferens (pA2 7.85), the guinea pig ileum (7.75), and the rat vas deferens (7.77). At high concentrations (10 microM), the compound was devoid of agonist activity in the mouse vas deferens and CHOhOP4, while it contracted the mouse colon and increased the twitch response of the rat vas deferens, and produced a naloxone-sensitive inhibition of the electrically evoked twitches in the guinea pig ileum. pA2 values for the new antagonist against deltorphin I in the mouse vas deferens (OP1 receptors), or against dermorphin in the guinea pig ileum (OP3 receptors), etorphine in the rat vas deferens (OP receptors), U69593 in the rabbit vas deferens (OP2 receptors) and endomorphin 1 in the mouse colon (OP3 receptors) were lower than 6. Taken together, these data indicate that J-113397 is a high-affinity, selective and competitive antagonist of the OP4 receptor; this novel pharmacological tool will be of great value in studies directed at evaluating the physiological roles of the nociceptin/OP4 system.     

Differentiation between rat brain and mouse vas deferens delta opioid receptors

Certain enkephalin analogues, including those which contain the conformationally restricted amino acid E-(2R,3S)-cyclopropylphenylalanine [2R,3S)-delta E Phe), have been shown to have high affinity for brain delta opioid receptors but are much less active in mouse vas deferens bioassays. To investigate whether there are differences between delta opioid receptors in brain and mouse was deferens, the ability of a selective delta opioid compound, [D-Pen2,pCl-Phe4,D-Pen5]enkephalin (pCl-DPDPE), and [D-Ala2,(2R,3S)-delta E Phe4,Leu5]enkephalin methyl ester (CP-OMe), to inhibit [3H]pCl-DPDPE binding in both rat brain and mouse vas deferens were measured. pCl-DPDPE recognized brain and mouse vas deferens binding sites with equal affinity, however, CP-OMe showed 33 fold lower affinity in mouse vas deferens compared to brain. This suggests that mouse vas deferens delta opioid receptors may be distinct from brain delta opioid receptors.     

Calcium modulatory properties of 2,6-dibutylbenzylamine (B25) in rat isolated vas deferens, cardiac and smooth muscle preparations.

1. In rat isolated vas deferens the new compound 2,6-dibutylbenzylamine (B25) evoked a series of repeating rhythmic contractions. Concentration-response curves constructed for this effect were bell-shaped, indicating a biphasic effect for this compound. By contrast, B25 depressed heart contractility without any visible positive inotropic or chronotropic activity. 2. Experiments with tetrodotoxin, reserpine, capsaicin, alpha-adrenoceptor blocking compounds and other agents permit us to exclude a release of neuromediators or a direct stimulation of post-synaptic receptors to account for the rhythmic effect of B25 in the rat vas deferens. 3. In the same tissue, the increase in 45Ca2+ uptake, the voltage-dependency as well as the dependence of the B25-induced rhythmic activity upon the external calcium concentration indicate a direct activation of voltage-sensitive calcium channels (VSCC). 4. Verapamil paradoxically stimulated the rhythmic effect of B25 in the rat vas deferens. La3+ was inactive while nifedipine was a weak inhibitor. By contrast Ni2+ and Mn2+ ions were good inhibitors (IC50 < 10(-4) M), suggesting that a possible opening of T-type VSCC underlies rhythmic effect of B25. 5. In radioligand binding studies competition experiments with [3H]-nitrendipine indicated that only at high concentrations was B25 able to interact with dihydropyridine-sensitive binding sites of heart and vas deferens smooth muscle. 6. B25 (3-30 microM) counteracted the inhibitory effects of omega-conotoxin GVIA in field-stimulated rat vas deferens.     

Alpha(1D)-adrenoceptors mediate nerve and agonist-evoked contractions in mouse vas deferens: evidence obtained from knockout technology

1 It has been demonstrated that nerve-evoked contractions of the rat vas deferens involve alpha(1D)-adrenoceptors. Definitive evidence for a similar alpha(1D)-adrenoceptor-mediated response in mouse vas deferens has been more difficult to obtain. In this study, we have used alpha(1D)-adrenoceptor knockout (alpha(1D)-KO) mice to aid in the pharmacological characterization. 2 Mouse whole vas deferens was stimulated with a single pulse every 5 min. Once a stable response had been obtained, vehicle or antagonist was administered cumulatively at 5-min intervals and a response to stimulation obtained 5 min later. Cumulative concentration-response curves were also obtained for noradrenaline. 3 In vas deferens from alpha(1D)-KO mice, the contractile response to low concentrations of noradrenaline and the contractile response to a single stimulus were significantly reduced as compared to wild type (WT). 4 The alpha(1D)-adrenoceptor selective antagonist, BMY 7378, produced a concentration-dependent inhibition of single pulse-evoked contractions of vas deferens from WT and alpha(1D)-KO mice. BMY 7378 was significantly less potent in inhibiting stimulation-evoked contractions in vas deferens from alpha(1D)-KO mice. 5 It is concluded that alpha(1D)-adrenoceptors mediate a component of nerve- and agonist-evoked contractions of the vas deferens of WT mice.     

Effects of denervation on the sensitizing effect to noradrenaline induced by morphine in the vas deferens of mice treated chronically with morphine

The acute administration of morphine to the isolated vas deferens from mice chronically exposed to this analgesic, induced a facilitatory effect on the responses of the muscle to exogenous noradrenaline. It has been suggested that this sensitizing property of morphine might reflect a dependence-like state of the vas deferens. In the present paper, the capability of met- and leu-enkephalin to substitute for morphine was studied, as well as the influence of innervation on the apparent dependence state. The contractile responses to noradrenaline and to acetylcholine were increased after the administration of morphine to the bath containing a denervated vas deferences, prepared from chronically morphinized mice. Morphine administration facilitated noradrenaline- but not acetylcholine-induced contractile effects in vas deferens isolated from mice which had been chronically treated with either morphine or morphine plus guanethidine. The presence of met- or leu-enkephalin in the isolated vas deferens from chronically morphinized mice (either intact, denervated or treated with guanethidine) failed to sensitize contractile responses to noradrenaline or acetylcholine. It is concluded that (a) the sensitizing effect induced by morphine in the vas deferens from mice chronically treated with morphine is specific for the adrenergic neurotransmitter; (b) the effect of morphine is not mimicked by opiate peptides; and (c) denervation of the vas deferens of mice treated chronically with morphine does not suppress the noradrenaline-sensitizing property of morphine.     

The effect of ethacrynic acid on the guinea-pig and rat isolated vas deferens

1 The effect of ethacrynic acid (EA) was studied on guinea-pig and rat vas deferens in vitro.2 EA contracted the guinea-pig but not the rat vas deferens in a dose-dependent manner (50-800 mug/ml). Tyramine caused contraction in 10 out of 18 guinea-pig vas deferens; EA caused contraction in 17 of the preparations which did not respond to tyramine. Repeated doses of EA produced tachyphylaxis, but there was no cross tachyphylaxis to tyramine.3 The contractions produced by EA were prevented by phentolamine or reserpine pretreatment and potentiated by cocaine. A low concentration of desipramine (3 ng/ml) potentiated and higher concentrations (0.6 and 3.0 mug/ml) inhibited the response of vas deferens to EA.4 Hexamethonium (100 mug/ml) or atropine (0.1 mug/ml) did not inhibit the effect of EA, excluding the nicotinic and muscarinic receptors as the sites of action.5 The effect of noradrenaline (NA) on the guinea-pig and rat vas deferens was enhanced by EA pretreatment, which may be due to inhibition of NA uptake.6 It is concluded that EA releases NA from guinea-pig vas deferens. The mechanism of release seems to be different from that of tyramine.     

β-Endorphin. Biological activity of analogs containing dermorphin and dynorphin sequences: ileum and vas deferens assays

Biological activity of synthetic β-endorphin (β-EP) analogs containing dermorphin or dynorphin-A-(1 – 13) structure has been investigated using the guinea pig ileum and the vas deferens of the mouse, rat and rabbit. Replacement of NH₂-terminal 1–7 segment of camel β-EP [β_c-EP-(1–7)] with dermorphin caused a great increase in opiate potency of the analog. [Dermorphin (1–7)] -β_c-EP was 120 times more potent than β_c-EP in the guinea pig ileum assay, 49 times more potent in the mouse vas deferens assay; and only 4 times more potent in the rat vas deferens assay. Replacement of NH₂-terminal 1–13 segment of human β-EP [β_h-EP-(1–13)] with dynorphin-A-(1–13) caused an increase in opiate potency in both the guinea pig ileum and rabbit vas deferens assays, a complete loss of potency in the rat vas deferens assay, and no change in the mouse vas deferens assay. In comparison with dynorphin-A-(1–13), the hybrid peptide was less potent in the guinea pig ileum assay as well as in mouse and rabbit vas deferens assay. It is suggested that β_c-EP-(8–31) facilitates the dermorphin moiety to act on opiate μ and δ receptors but not on the ± receptor, while β_h-(14–31) reduces the action of dynorphin on μ, δ and k receptors.     

The effects of ethanol dependence on drug responsiveness of mouse isolated vas deferens

The effects of ethanol dependence on the responsiveness of the mouse vas deferens to noradrenaline (NA), carbachol, barium and calcium were studied. Ethanol dependence increases the maximum responses to NA and carbachol whereas responsiveness to barium remains unaltered. The concentration-effect curve to calcium was shifted to the left (3.0-fold at the EC50 level). It is concluded that in vas deferens isolated from ethanol-dependent mice the increased responsiveness to NA, carbachol and calcium is a consequence of an enhanced calcium entry through voltage-independent calcium channels, as it has been reported for brain tissue.     

Effects of Ro 64-6198 in nociceptin/orphanin FQ-sensitive isolated tissues

The pharmacological profile of the non-peptide OP4 receptor (ORL1, LC132) agonist, Ro 64-6198, was investigated, in three electrically stimulated nociceptin/orphanin FQ (NC)-sensitive preparations, namely the mouse and rat vas deferens and the guinea pig ileum. Ro 64-6198 mimicked the inhibitory effect of NC in the three preparations, while showing slow kinetics of action and a slowly reversible effect compared to the fast and immediately and completely reversible effect of the natural peptide. Ro 64-6198 displayed similar pEC50 and Emax values as NC in the mouse and rat vas deferens while it was 100-fold less potent but more efficacious (higher Emax) than NC in the guinea pig ileum. In the rat vas deferens the effects of Ro 64-6198 were antagonised by [Nphe1]NC(1-13)NH2 and J-113397 with pKB values (6.30 and 8.05, respectively) similar to those obtained against NC (6.20 and 7.77, respectively). Naloxone (1 microM) was inactive. In the guinea pig ileum a clear shift of the concentration response curve to Ro 64-6198 was obtained only using a cocktail of antagonists (naloxone + [Nphe1]NC(1-13)NH2 or naloxone + J-113397). In the mouse vas deferens the antagonists were inactive against Ro 64-6198 either when tested alone or in combination. Therefore, Ro 64-6198 behaved as a selective OP4 receptor agonist only in the rat tissue. These results suggest a physiological heterogeneity in OP4 receptors across tissues and species and may explain why, when tested in vivo, Ro 64-6198 mimics the potent anxiolytic effect of NC better in the rat than in the mouse.     

Stimulation frequency-noradrenaline release relationships examined in α2A-, α2B- and α2C-adrenoceptor-deficient mice

The stimulation frequency-noradrenaline release relationship was studied in the vas deferens and the cerebral cortex of NMRI mice, mice in which the alpha2A-, the alpha2B-, the alpha2C- or both the alphaCA- and the alpha2C-adrenoceptor gene had been disrupted (alpha2AKO, alpha2BKO, alpha2CKO and alpha2ACKO), and the wildtype mice from which the knockout animals had been generated. Tissue pieces were preincubated with 3H-noradrenaline and then superfused and stimulated electrically with a constant number of pulses (30 in vas deferens and 50 in brain cortex) at frequencies between 0.03 and 100 Hz. The frequency-evoked tritium overflow curves ascended monophasically in the vas deferens of wildtype and NMRI mice. Disruption of the alpha2B-adrenoceptor gene caused no change. In the vas deferens of alpha2CKO mice, the overflow evoked by low frequencies (0.3 and 1 Hz) was slightly increased. In the vas deferens of alpha2AKO and alpha2ACKO mice, the evoked overflow was increased to a greater extent. Rauwolscine (1 microM) caused a marked increase of the evoked overflow of tritium from the vas deferens of NMRI, wildtype, alpha2BKO and alpha2CKO mice. Rauwolscine also increased the evoked overflow of tritium from the vas deferens of alpha2AKO and alphaC2ACKO mice, but to a smaller extent. The gene disruptions and rauwolscine slightly steepened the slope of the vas deferens frequency-overflow curve. In the brain cortex of wildtype and NMRI mice, the frequency-evoked tritium overflow curves were U-shaped. In the brain cortex of alpha2BKO and alpha2CKO mice, the evoked overflow was slightly reduced. In the brain cortex of alpha2AKO and alpha2AcKO mice, in contrast, the evoked overflow was increased. Rauwolscine (1 microM) caused a marked increase of the evoked overflow of tritium from the brain cortex of NMRI, wildtype, Q2BKO and alpha2CKO mice. Rauwolscine also increased the evoked overflow of tritium from the brain cortex of alpha2AKO and alpha2ACKO mice, but to a smaller extent. The gene disruptions and rauwolscine flattened the U shape of the brain cortex frequency-overflow curve. It is concluded that alpha2-autoinhibition is one factor that shapes the frequency-noradrenaline release relationships in the mouse vas deferens and cerebral cortex. The autoreceptors are mainly alpha2A and to a minor extent, and well detectable in the vas deferens only, alpha2C. When both the alpha2A- and the alpha2C-adrenoceptor have been deleted, alpha2B-adrenoceptors may be expressed as autoreceptors in noradrenergic neurons. It seems possible that alpha2C-autoreceptors depress mainly release at low (around 1 Hz) whereas alpha2A-autoreceptors depress mainly release at high (around 10 Hz) frequencies.