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151.
Currently utilized antidepressants have limited effectiveness and frequently incur undesired effects. Most antidepressants are thought to act via the inhibition of monoamine reuptake; however, direct binding to monoaminergic receptors has been proposed to contribute to both their clinical effectiveness and their side effects, or lack thereof. Among the target receptors of antidepressants, α1‑adrenergic receptors (ARs) have been implicated in depression etiology, antidepressant action, and side effects. However, differences in the direct effects of antidepressants on signaling from the three subtypes of α1-ARs, namely, α1A-, α1B- and α1D‑ARs, have been little explored. We utilized cell lines overexpressing α1A-, α1B- or α1D-ARs to investigate the effects of the antidepressants imipramine (IMI), desipramine (DMI), mianserin (MIA), reboxetine (REB), citalopram (CIT) and fluoxetine (FLU) on noradrenaline-induced second messenger generation by those receptors. We found similar orders of inhibition at α1A-AR (IMI < DMI < CIT < MIA < REB) and α1D‑AR (IMI = DMI < CIT < MIA), while the α1B-AR subtype was the least engaged subtype and was inhibited with low potency by three drugs (MIA < IMI = DMI). In contrast to their direct antagonistic effects, prolonged incubation with IMI and DMI increased the maximal response of the α1B-AR subtype, and the CIT of both the α1A- and the α1B-ARs. Our data demonstrate a complex, subtype-specific modulation of α1-ARs by antidepressants of different groups.  相似文献   
152.
Dry eye disease (DED) is commonly associated with ocular surface inflammation and pain. In this study, we evaluated the effectiveness of repeated instillations of transient receptor potential melastatin 8 (TRPM8) ion channel antagonist M8-B on a mouse model of severe DED induced by the excision of extra-orbital lacrimal and Harderian glands. M8-B was topically administered twice a day from day 7 until day 21 after surgery. Cold and mechanical corneal sensitivities and spontaneous ocular pain were monitored at day 21. Ongoing and cold-evoked ciliary nerve activities were next evaluated by electrophysiological multi-unit extracellular recording. Corneal inflammation and expression of genes related to neuropathic pain and inflammation were assessed in the trigeminal ganglion. We found that DED mice developed a cold allodynia consistent with higher TRPM8 mRNA expression in the trigeminal ganglion (TG). Chronic M8-B instillations markedly reversed both the corneal mechanical allodynia and spontaneous ocular pain commonly associated with persistent DED. M8-B instillations also diminished the sustained spontaneous and cold-evoked ciliary nerve activities observed in DED mice as well as inflammation in the cornea and TG. Overall, our study provides new insight into the effectiveness of TRPM8 blockade for alleviating corneal pain syndrome associated with severe DED, opening a new avenue for ocular pain management.  相似文献   
153.
李荀  王东华  胡清萍  崔学桂 《精细化工》2004,21(7):519-520,528
设计并合成了化合物1 烯丙基 6 氯 7 甲基 1,4 二氢喹喔啉 2,3 二酮,该化合物主要用于一系列新型NMDA受体拮抗剂的制备。反应以1 氯 4 氟 2 甲基苯为原料,在浓硫酸溶液中采用硝酸钾硝化得1 氯 4 氟 2 甲基 5 硝基苯,收率94 0%,将1 氯 4 氟 2 甲基 5 硝基苯与烯丙胺反应,三乙胺为缚酸剂,回流反应合成烯丙基 (4 氯 5 甲基 2 硝基 苯基) 胺,收率为81 0%,然后使用铁粉高收率还原所得的硝基化合物(收率为95 0%),再与二水合草酸在c(HCl)=2mol/L的盐酸中进行环合反应合成目的化合物1 烯丙基 6 氯 7 甲基 1,4 二氢喹喔啉 2,3 二酮(收率为90 6%),反应总收率为65 5%。  相似文献   
154.
Targeting cannabinoid 1 receptors (CB1R) with peripherally restricted antagonists (or inverse agonists) shows promise to improve metabolic disorders associated with obesity. In this context, we designed and synthetized JM-00266, a new CB1R blocker with limited blood–brain barrier (BBB) permeability. Pharmacokinetics were tested with SwissADME and in vivo in rodents after oral and intraperitoneal administration of JM-00266 in comparison with Rimonabant. In silico predictions indicated JM-00266 is a non-brain penetrant compound and this was confirmed by brain/plasma ratios and brain uptake index values. JM-00266 had no impact on food intake, anxiety-related behavior and body temperature suggesting an absence of central activity. cAMP assays performed in CB1R-transfected HEK293T/17 cells showed that the drug exhibited inverse agonist activity on CB1R. In addition, JM-00266 counteracted anandamide-induced gastroparesis indicating substantial peripheral activity. Acute administration of JM-00266 also improved glucose tolerance and insulin sensitivity in wild-type mice, but not in CB1R−/− mice. Furthermore, the accumulation of JM-00266 in adipose tissue was associated with an increase in lipolysis. In conclusion, JM-00266 or derivatives can be predicted as a new candidate for modulating peripheral endocannabinoid activity and improving obesity-related metabolic disorders.  相似文献   
155.
Transient receptor potential melastatin type 8 (TRPM8) is a target for the treatment of different physio-pathological processes. While TRPM8 antagonists are reported as potential drugs for pain, cancer, and inflammation, to date only a limited number of chemotypes have been investigated and thus a limited number of compounds have reached clinical trials. Hence there is high value in searching for new TRPM8 antagonistic to broaden clues to structure-activity relationships, improve pharmacological properties and explore underlying molecular mechanisms. To address this, the EDASA Scientific in-house molecular library has been screened in silico, leading to identifying twenty-one potentially antagonist compounds of TRPM8. Calcium fluorometric assays were used to validate the in-silico hypothesis and assess compound selectivity. Four compounds were identified as selective TRPM8 antagonists, of which two were dual-acting TRPM8/TRPV1 modulators. The most potent TRPM8 antagonists (BB 0322703 and BB 0322720) underwent molecular modelling studies to highlight key structural features responsible for drug–protein interaction. The two compounds were also investigated by patch-clamp assays, confirming low micromolar potencies. The most potent compound (BB 0322703, IC50 1.25 ± 0.26 μM) was then profiled in vivo in a cold allodinya model, showing pharmacological efficacy at 30 μM dose. The new chemotypes identified showed remarkable pharmacological properties paving the way to further investigations for drug discovery and pharmacological purposes.  相似文献   
156.
拮抗微生物诱导采后果蔬抗病性的机制   总被引:1,自引:0,他引:1  
罗杨  明建  曾凯芳 《食品科学》2010,31(9):297-300
综述拮抗微生物诱导采后果蔬抗病性的机制。拮抗微生物能够诱导果蔬产生植物保卫素,提高果蔬防御酶如几丁质酶、β -1,3- 葡聚糖酶、苯丙氨酸解氨酶、过氧化物酶和多酚氧化酶的活性,并能够通过调节活性氧代谢和提高果蔬结构抗性,从而增强果蔬的抗病性。拮抗微生物诱导采后果蔬抗病性的机制研究将为生物防治技术在采后果蔬病害防治中的应用提供参考依据。  相似文献   
157.
采用比较分子场分析(comparative molecular field analysis,CoMFA)方法研究了两组促肾上腺皮质激素释放因子(cortico- tropin releasing factor,CRF)受体抑制剂的结构与活性关系。所得的CoMFA模型具有较好的稳定性和预报能力,q~2和r~2值分别为0.515和0.970。通过分析分子场等势图,可以直观地观察到分子周围的立体和静电特征对化合物特性的影响,为设计高活性CRF抑制剂提供了理论依据。  相似文献   
158.
159.
植物激素主要包括激动剂和拮抗剂二大类。对乙烯、赤霉素和茉莉酸的激动剂和拮抗剂及它们的生理作用分别予以介绍。  相似文献   
160.
缬沙坦是第一个不含咪唑环的非肤类血管紧张素II受体拮抗剂,拈抗活性强、半褒期长,引人关注,其应用前景十分广阔,市场潜力十分巨大。文章介绍了缬沙坦的各种合成方法,综合比较了各种合成方法的利弊,并分析了缬沙坦合成的国内外研究现状和发展趋势。  相似文献   
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