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排序方式: 共有1520条查询结果,搜索用时 15 毫秒
1.
Jacqueline D. Keighron JoLynn B. Giancola Rachel J. Shaffer Emily M. DeMarco Mark A. Coggiano Rachel D. Slack Amy Hauck Newman Gianluigi Tanda 《The European journal of neuroscience》2019,50(3):2045-2053
Psychostimulant use disorders remain an unabated public health concern worldwide, but no FDA approved medications are currently available for treatment. Modafinil (MOD), like cocaine, is a dopamine reuptake inhibitor and one of the few drugs evaluated in clinical trials that has shown promise for the treatment of cocaine or methamphetamine use disorders in some patient subpopulations. Recent structure–activity relationship and preclinical studies on a series of MOD analogs have provided insight into modifications of its chemical structure that may lead to advancements in clinical efficacy. Here, we have tested the effects of the clinically available (R)‐enantiomer of MOD on extracellular dopamine levels in the nucleus accumbens shell, a mesolimbic dopaminergic projection field that plays significant roles in various aspects of psychostimulant use disorders, measured in vivo by fast‐scan cyclic voltammetry and by microdialysis in Sprague‐Dawley rats. We have compared these results with those obtained under identical experimental conditions with two novel and enantiopure bis(F) analogs of MOD, JBG1‐048 and JBG1‐049. The results show that (R)‐modafinil (R‐MOD), JBG1‐048, and JBG1‐049, when administered intravenously with cumulative drug‐doses, will block the dopamine transporter and reduce the clearance rate of dopamine, increasing its extracellular levels. Differences among the compounds in their maximum stimulation of dopamine levels, and in their time course of effects were also observed. These data highlight the mechanistic underpinnings of R‐MOD and its bis(F) analogs as pharmacological tools to guide the discovery of novel medications to treat psychostimulant use disorders. 相似文献
2.
Alberto Addis Maxime Gaasch Alois J Schiefecker Mario Kofler Bogdan Ianosi Verena Rass Anna Lindner Gregor Broessner Ronny Beer Bettina Pfausler Claudius Thom Erich Schmutzhard Raimund Helbok 《Journal of cerebral blood flow and metabolism》2021,41(2):359
Elevated body temperature (Tcore) is associated with poor outcome after subarachnoid hemorrhage (SAH). Brain temperature (Tbrain) is usually higher than Tcore. However, the implication of this difference (Tdelta) remains unclear. We aimed to study factors associated with higher Tdelta and its association with outcome. We included 46 SAH patients undergoing multimodal neuromonitoring, for a total of 7879 h of averaged data of Tcore, Tbrain, cerebral blood flow, cerebral perfusion pressure, intracranial pressure and cerebral metabolism (CMD). Three-months good functional outcome was defined as modified Rankin Scale ≤2. Tbrain was tightly correlated with Tcore (r = 0.948, p < 0.01), and was higher in 73.7% of neuromonitoring time (Tdelta +0.18°C, IQR −0.01 – 0.37°C). A higher Tdelta was associated with better metabolic state, indicated by lower CMD-glutamate (p = 0.003) and CMD-lactate (p < 0.001), and lower risk of mitochondrial dysfunction (MD) (OR = 0.2, p < 0.001). During MD, Tdelta was significantly lower (0°C, IQR −0.2 – 0.1; p < 0.001). A higher Tdelta was associated with improved outcome (OR = 7.7, p = 0.002). Our study suggests that Tbrain is associated with brain metabolic activity and exceeds Tcore when mitochondrial function is preserved. Further studies are needed to understand how Tdelta may serve as a surrogate marker for brain function and predict clinical course and outcome after SAH. 相似文献
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4.
Aging is associated with an enhanced neuroinflammatory response to acute immune challenge, often termed “inflammaging.” However, there are conflicting reports about whether baseline levels of inflammatory markers are elevated under ambient conditions in the aging brain, or whether such changes are observed predominantly in response to acute challenge. The present studies utilized two distinct approaches to assess inflammatory markers in young and aging Fischer 344 rats. Experiment 1 examined total tissue content of inflammatory markers from hippocampus of adult (3 month), middle-aged (12 month), and aging (18 month) male Fischer (F) 344 rats using multiplex analysis (23-plex). Though trends emerged for several cytokines, no significant differences in basal tissue content were observed across the 3 ages examined. Experiment 2 measured extracellular concentrations of inflammatory factors in the hippocampus from adult (3 month) and aging (18 month) males and females using large-molecule in vivo microdialysis. Although few significant aging-related changes were observed, robust sex differences were observed in extracellular concentrations of CCL3, CCL20, and IL-1α. Experiment 2 also evaluated the involvement of the P2X7 purinergic receptor in neuroinflammation using reverse dialysis of the selective agonist BzATP. BzATP produced an increase in IL-1α and IL-1β release and rapidly suppressed the release of CXCL1, CCL2, CCL3, CCL20, and IL-6. Other noteworthy sex by aging trends were observed in CCL3, IL-1β, and IL-6. Together, these findings provide important new insight into late-aging and sex differences in neuroinflammation, and their regulation by the P2X7 receptor. 相似文献
5.
Asuka Ito Mostofa Jamal Kiyoshi Ameno Naoko Tanaka Ayaka Takakura Takanori Miki 《Drug and chemical toxicology》2018,41(2):245-247
Carbon monoxide (CO) produces several neurological effects, including cognitive, mood, and behavioral disturbance. Glutamate is thought to play a particularly important role in learning and memory. Thus, the present study was aimed at investigating the local effect of CO on the glutamate level in the hippocampus of mice using in vivo reverse microdialysis. Mice were perfused with Ringer’s solution (control) or CO (60–125?μM) in Ringer’s solution into the hippocampus via microdialysis probe. Dialysate samples were collected every 20?min, and then analyzed with high-performance liquid chromatography coupled to an electrochemical detector. The result revealed that the perfusion with CO had no significant effect on glutamate levels (p?=?0.316) as compared to the control group. This finding does not support a local CO rise as the cause of the increased glutamate level in the hippocampus of mice. 相似文献
6.
为进一步研究黄芩苷的入脑行为及脑细胞间液药代动力学,对黄芩苷在脑、血微透析探针的体内外回收率及其稳定性进行了研究。采用LC-MS/MS测定脑、血微透析液中黄芩苷的浓度,计算探针回收率;分别采用增量法、减量法考察不同流速(0.50,1.0,1.5,2.0,3.0μL·min~(-1))对探针体外回收率的影响;采用增量法考察不同浓度(50.00,200.0,500.0,1 000μg·L~(-1))、探针使用次数(0,1,2)对体外回收率的影响;采用减量法考察在大鼠体内探针回收率稳定性及流速对回收率的影响,并与体外结果进行比较。在同一浓度下,黄芩苷的脑、血探针体外回收率均随着流速的增加而降低;在同一流速下,探针回收率与黄芩苷的浓度无关;使用后并经过恢复处理的脑、血探针,在使用2次后,探针的回收率没有明显的变化;增量法和减量法所测得的体外回收率基本相同;减量法测得的体内回收率与体外结果相近,且脑、血探针体内回收率在10 h内的稳定性均良好。研究结果表明减量法能够作为研究黄芩苷体内回收率的测定方法,微透析技术能够用于黄芩苷在脑细胞间液药代动力学、血液药代动力学的同步研究。 相似文献
7.
目的:考察制川乌对白芍中芍药苷经皮转运的影响,从经皮转运角度研究制川乌-白芍配伍协同增效作用机制。方法:以昆明种清洁级小鼠为实验对象,分别经皮给予白芍凝胶、制川乌-白芍凝胶和白芍-氮酮凝胶,采用皮肤微透析取样技术,建立HPLC测定透析液中芍药苷的浓度,流动相乙腈-0.1%磷酸水溶液(14∶86),检测波长230 nm;利用DAS 2.0软件计算局部药动学参数,采用扫描电镜考察药物对小鼠皮肤角质层的影响。结果:白芍凝胶组的药时曲线下面积(AUC_(0-t)),平均滞留时间(MRT_(0-t)),半衰期(t_(1/2)),达峰时间(T_(max))和药峰浓度(C_(max))分别为(3.28±1.01)mg·L~(-1)·h,(3.95±0.32)h,(0.92±0.44)h,(2.00±0)h和(0.72±0.24)mg·L~(-1);白芍-制川乌凝胶组MRT_(0-t),AUC_(0-t),t_(1/2),T_(max)和C_(max)分别为(3.35±0.08)h,(10.64±1.24)mg·L~(-1)·h,(1.32±0.67)h,(1.00±0)h和(3.06±0.38)mg·L~(-1),白芍-氮酮凝胶组AUC_(0-t),MRT_(0-t),t_(1/2),T_(max),C_(max)分别为(59.82±13.51)mg·L~(-1)·h,(3.67±0.08)h,(0.89±0.16)h,(2.67±0.29)h和(13.24±4.14)mg·L~(-1)。与白芍凝胶组比较,制川乌-白芍凝胶组AUC_(0-t)和C_(max)均显著增大,T_(max)明显缩短。扫描电镜观察结果表明制川乌作用皮肤后,角质层细胞间隙明显增加,且与氮酮对皮肤的作用类似。结论:制川乌-白芍配伍能显著提高芍药苷的透皮吸收,达到配伍"增效"的目的,这可能与制川乌降低角质层的屏障作用有关。 相似文献
8.
L‐DOPA‐induced dyskinesia in a rat model of Parkinson's disease is associated with the fluctuational release of norepinephrine in the sensorimotor striatum 下载免费PDF全文
Yong Wang Hui Sheng Wang Tao Wang Chen Huang Jian Liu 《Journal of neuroscience research》2014,92(12):1733-1745
L‐3,4‐dihydroxyphenylalanine (L‐DOPA)‐induced dyskinesia (LID) is the most common complication of standard L‐DOPA therapy for Parkinson's disease experienced by most parkinsonian patients. LID is associated with disruption of dopaminergic homeostasis in basal ganglia following L‐DOPA administration. Norepinephrine (NE) is another important catecholaminergic neurotransmitter that is also believed to be involved in the pathogenesis of LID. This study compared NE release in the ipsilateral sensorimotor striatum of dyskinetic and nondyskinetic 6‐hydroxydopamine‐lesioned hemiparkinsonian rats treated chronically with L‐DOPA. After L‐DOPA injection, the time‐course curves of NE levels in the sensorimotor striatum were significantly different between dyskinetic and nondyskinetic rats. Several metabolic kinetic parameters of NE levels were also differentially expressed between the two groups. In comparison with nondyskinetic rats, the ΔCmax of NE was significantly higher in dyskinetic rats, whereas Tmax and t1/2 of NE were significantly shorter. Intrastriatal perfusion of NE into the lesioned sensorimotor striatum revealed a moderate dyskinesia in dyskinetic rats, which was similar to the dyskinetic behavior after L‐DOPA administration. The L‐DOPA‐related dyskinetic behavior was inhibited significantly by a further pretreatment of noradrenergic neurotoxin N‐?(2‐?chloroethyl)?‐?N‐?ethyl‐?2‐?bromobenzylamine or intrastriatal administration of the α2‐adrenoceptor antagonist idazoxan, accompanied by significant changes in metabolic kinetic parameters of NE in the sensorimotor striatum. The results provide evidence to support the correlation between abnormal NE neurotransmission and the induction of LID and suggest that the aberrant change of the quantitative and temporal releasing of NE in the sensorimotor striatum might play an important role in the pathogenesis of LID. © 2014 Wiley Periodicals, Inc. 相似文献
9.
Wayne G. Brake 《The European journal of neuroscience》2014,39(2):257-265
Estrogen has been shown to enhance the effects of antipsychotics in humans. To investigate the mechanisms of how this may occur, the current study examined estradiol's effects on dopaminergic transmission and behavior in amphetamine‐sensitized and non‐sensitized female rats. Sixty‐four ovariectomized female Sprague–Dawley rats were used for this study. Half of the rats were sensitized to four once‐daily injections of 1 mg/kg amphetamine and the other half served as controls. Rats received chronic administration of either low‐dose haloperidol (0.25 mg/kg/day) or saline vehicle via osmotic minipumps implanted subcutaneously. The groups were further subdivided with respect to estradiol treatment: low chronic estrogen (subcutaneous estradiol implant, 0.36 mg/pellet: 90‐day release, plus an additional oil vehicle injection every second day) and high pulsatile estrogen (subcutaneous estradiol implant plus an additional 10 μg/kg estradiol injection every second day). Motor activity was assessed at day 2 and day 12 during haloperidol treatment, while nucleus accumbens dopamine availability was assessed via microdialysis 10 days into antipsychotic treatment. Haloperidol treatment along with high, but not low, estradiol replacement was effective in reducing amphetamine‐induced locomotor activity in sensitized rats. High estradiol treatment also augmented the effects of chronic haloperidol in reducing dopaminergic release in sensitized rats. These data suggest that estradiol levels affect both the behavioral and the dopamine responses to chronic antipsychotic treatment. 相似文献
10.
Mark Ellebæk Niels QvistClaus Fristrup M.D. Ph.D. Michael B. Mortensen M.D. Ph.D. D.M.Sc. 《American journal of surgery》2014