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排序方式: 共有381条查询结果,搜索用时 15 毫秒
1.
Patricia Seoane-Collazo Amparo Romero-Pic Eva Rial-Pensado Laura Liares-Pose nxela Estvez-Salguero Johan Fern Rubn Nogueiras Carlos Diguez Miguel Lpez 《International journal of molecular sciences》2021,22(4)
Several studies have reported that nicotine, the main bioactive component of tobacco, exerts a marked negative energy balance. Apart from its anorectic action, nicotine also modulates energy expenditure, by regulating brown adipose tissue (BAT) thermogenesis and white adipose tissue (WAT) browning. These effects are mainly controlled at the central level by modulation of hypothalamic neuropeptide systems and energy sensors, such as AMP-activated protein kinase (AMPK). In this study, we aimed to investigate the kappa opioid receptor (κOR)/dynorphin signaling in the modulation of nicotine’s effects on energy balance. We found that body weight loss after nicotine treatment is associated with a down-regulation of the κOR endogenous ligand dynorphin precursor and with a marked reduction in κOR signaling and the p70 S6 kinase/ribosomal protein S6 (S6K/rpS6) pathway in the lateral hypothalamic area (LHA). The inhibition of these pathways by nicotine was completely blunted in κOR deficient mice, after central pharmacological blockade of κOR, and in rodents where κOR was genetically knocked down specifically in the LHA. Moreover, κOR-mediated nicotine effects on body weight do not depend on orexin. These data unravel a new central regulatory pathway modulating nicotine’s effects on energy balance. 相似文献
2.
以尼古丁为研究对象 ,研制了一系列含有不同增塑剂 (苯二甲酸二辛酯、苯二甲酸二壬酯和癸二酸二辛酯 )和电活性物质 (尼古丁 四苯硼缔合物、尼古丁 硅钨酸缔合物、尼古丁 磷钨酸缔合物和尼古丁 雷氏盐缔合物 )的PVC膜电极。所有的 8支电极均对尼古丁盐酸溶液有Nernst响应。所制备的电极中 ,以尼古丁 四苯硼缔合物、尼古丁 硅钨酸缔合物、尼古丁 磷钨酸缔合物或尼古丁 雷氏盐缔合物为活性物的电极 ,其线性范围达到 10 - 4~ 10 - 1 mol/L ,以尼古丁 硅钨酸缔合物为活性物的电极线性范围达到 10 - 5~ 10 - 1 mol/L。电极响应的均匀性还在进一步的研究和改善中 相似文献
3.
Piasecki Thomas M.; Jorenby Douglas E.; Smith Stevens S.; Fiore Michael C.; Baker Timothy B. 《Canadian Metallurgical Quarterly》2003,11(4):276
Five parameters of postcessation smoking withdrawal variability derived from clinical data (T. M. Piasecki, D. E. Jorenby, S. S. Smith, M. C. Fiore, & T. B. Baker, 2003a, 2003b) were predicted from baseline measures and pharmacotherapy assignment. Smokers who were more dependent, older, and high in negative affect reported more severe withdrawal. Women, heavier smokers, and those with a history of depression reported more variable symptoms. Smokers treated with nicotine patch, bupropion, or both reported less severe withdrawal than did those given placebo, but medication did not affect the slope of symptoms over time, day-to-day variability of symptoms, or the size of acute changes in symptoms associated with lapses to smoking. Prior research has shown that these symptom facets predict later relapse: thus, current pharmacotherapies may aid cessation by diminishing withdrawal severity, but they do not affect all clinically important aspects of withdrawal. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
超声提取-高效液相色谱法测定烟草中烟碱含量 总被引:4,自引:0,他引:4
确定了制备烟碱分析样品的超声波提取条件:0.4% NaOH溶液为溶剂,液固比40:1(mL·g-1),提取时间4 h.确定了高效液相色谱法检测烟碱含量的条件为Kromasil C18色谱柱(250 mm×4.6 mm,5 μm),检测波长259 nm,检测温度35 ℃,流动相CH3OH/0.02 mol·L-1磷酸盐缓冲溶液(V/V)为60/40,流速1.0 mL·min-1,进样量10 μL.平均加样回收率98.8%,相对标准偏差1.2%.结果表明超声提取-高效液相色谱法是一种准确度高,速度快的测定烟草中烟碱含量的检测方法. 相似文献
5.
6.
We examined the effects of inhibitors of the octadecanoid pathway (n-propyl gallate, acetosalicylic acid, salicylhydroxamic acid, methyl salicylate, and antipyrine) on wound- and jasmonate-induced nicotine accumulation and compared the nicotine-inducing ability of exogeneous additions of linolenic acid (18:3) and its methyl ester, linoleic acid (18:2), abscisic acid, traumatic acid, and methyl dihydrojasmonate to the nicotine-inducing ability of exogenous additions of methyl jasmonate (MJ). The first four of these inhibitors significantly reduced wound-induced nicotine accumulation when applied in a lanolin paste to wounded tissues immediately after wounding at concentrations of 89–90µg/plant. When methyl salicylate and propyl gallate were mixed individually with MJ, neither inhibited MJ-induced nicotine synthesis, which suggests that the inhibitors block jasmonate synthesis or release from stored pools and not its effects. Linolenic acid or its methyl ester applied to undamaged plants or damaged plants (to either damaged or undamaged leaves) or to the roots of hydroponically growing plants did not induce nicotine accumulation or increase nicotine accumulation above levels found in damaged plants. Similarly, traumatic acid, linoleic acid, and abscisic acid did not induce nicotine accumulations. Methyl dihydrojasmonate, which is biosynthetically derived from linoleic acid, had 12–56% of the nicotine-inducing acitivity of MJ when added to the roots of hydroponically grown plants. The signal transduction pathway mediating wound-induced nicotine production therefore shares many features of the pathway eliciting wound-induced proteinase inhibitor production but differs in not being regulated at the lipase step in jasmonic acid production and not being responsive to abscisic acid. 相似文献
7.
Kalman David; Kahler Christopher W.; Tirch Dennis; Kaschub Cynthia; Penk Walter; Monti Peter M. 《Canadian Metallurgical Quarterly》2004,18(1):78
This study reports findings from an investigation of the efficacy of high-dose nicotine patch (NP) therapy for heavy smokers with a past history of alcohol dependence. One hundred thirty participants were randomly assigned to 42 mg or 21 mg of transdermal nicotine for 4 weeks, followed by an 8-week dose titration. Follow-up assessments were conducted at 4 and 12 weeks. Differences between dose conditions were nonsignificant, although unexpectedly, outcomes favored participants in the 21-mg NP condition. Nicotine abstinence at follow-up was related to longer length of alcohol abstinence at time of enrollment. Future research should investigate ways to improve smoking quit rates in this population, including more frequent counseling sessions and/or other pharmacotherapies. These investigations should focus primarily on smokers in early alcohol recovery. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
9.
Yong Li Yanyan Zhang Andrew Walayat Yingjie Fu Bailin Liu Lubo Zhang Daliao Xiao 《International journal of molecular sciences》2022,23(13)
Nicotine exposure either from maternal cigarette smoking or e-cigarette vaping is one of the most common risk factors for neurodevelopmental disease in offspring. Previous studies revealed that perinatal nicotine exposure programs a sensitive phenotype to neonatal hypoxic-ischemic encephalopathy (HIE) in postnatal life, yet the underlying mechanisms remain undetermined. The goal of the present study was to determine the regulatory role of H19/miR-181a/ATG5 signaling in perinatal nicotine exposure-induced development of neonatal brain hypoxic-ischemic sensitive phenotype. Nicotine was administered to pregnant rats via subcutaneous osmotic minipumps. All experiments were conducted in offspring pups at postnatal day 9 (P9). Perinatal nicotine exposure significantly enhanced expression of miR-181a but attenuated autophagy-related protein 5 (ATG5) mRNA and protein levels in neonatal brains. Of interest, miR-181a mimicking administration in the absence of nicotine exposure also produced dose-dependent increased hypoxia/ischemia (H/I)-induced brain injury associated with a decreased ATG5 expression, closely resembling perinatal nicotine exposure-mediated effects. Locked nucleic acid (LNA)-miR-181a antisense reversed perinatal nicotine-mediated increase in H/I-induced brain injury and normalized aberrant ATG5 expression. In addition, nicotine exposure attenuated a long non-coding RNA (lncRNA) H19 expression level. Knockdown of H19 via siRNA increased the miR-181a level and enhanced H/I-induced neonatal brain injury. In conclusion, the present findings provide a novel mechanism that aberrant alteration of the H19/miR-181a/AGT5 axis plays a vital role in perinatal nicotine exposure-mediated ischemia-sensitive phenotype in offspring and suggests promising molecular targets for intervention and rescuing nicotine-induced adverse programming effects in offspring. 相似文献
10.