Search results for "Phenylacetic acid"

2021

The hydrophobic tails of aliphatic primary alcohols do insert into the hydrophobic core of a lipid bilayer. Thereby, they disrupt hydrophobic interactions between the lipid molecules, resulting in a decreased lipid order, i.e., an increased membrane fluidity. While aromatic alcohols, such as 2-phenylethanol, also insert into lipid bilayers and disturb the membrane organization, the impact of aromatic alcohols on the structure of biological membranes, as well as the potential physiological implication of membrane incorporation has only been studied to a limited extent. Although diverse targets are discussed to be causing the bacteriostatic and bactericidal activity of 2-phenylethanol, it is …

Influence of St John's wort on catecholamine turnover and cardiovascular regulation in humans

2004

BACKGROUND: St John's wort (Hypericum perforatum) is a popular over-the-counter antidepressant. Its antidepressive effect has been attributed in part to inhibition of monoamine transporters and monoamine oxidase, on the basis of in vitro studies. METHODS: In a double-blind, randomized, placebo-controlled, crossover study, 16 healthy subjects (11 men and 5 women; mean age, 31 +/- 5 years) ingested either St John's wort (300 mg three times daily) or placebo for 7 days. Imipramine treatment (50 mg three times daily) in 7 subjects served as a positive control. After treatment, physiologic and biochemical tests included cardiovascular reflex testing, graded head-up tilt testing, and plasma catec…

Relationship between dopamine D2 receptor occupancy, clinical response, and drug and monoamine metabolites levels in plasma and cerebrospinal fluid. …

2009

Combining measurements of the monoamine metabolites in the cerebrospinal fluid (CSF) and neuroimaging can increase efficiency of drug discovery for treatment of brain disorders. To address this question, we examined five drug-naive patients suffering from schizophrenic disorder. Patients were assessed clinically, using the Positive and Negative Syndrome Scale (PANSS): at baseline and then at weekly intervals. Plasma and CSF levels of quetiapine and norquetiapine as well CSF 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), 5-hydroxyindole-acetic acid (5-HIAA) and 3-methoxy-4-hydroxyphenylglycol (MHPG) were obtained at baseline and again after at least a 4 week medication trai…

Effect of electron-withdrawing substituents on the electrophilicity of carbonyl carbons

2005

Indexación: Scopus The substituent effects on the carbonyl carbon atom for a series of twelve substituted phenyl acetates have been rationalized using a global electrophilicity index. This index is linearly correlated with the experimental reaction rate coefficients. We found that, in contrast to the proposed interpretation based on experimental 13C NMR chemical shifts and ground state destabilization calculations, the electrophilicity of carbonyl compounds increases due to the effect promoted by electron-withdrawing groups in these systems. https://www.sciencedirect.com/science/article/pii/S0040402004018046?via%3Dihub

Total synthesis of two potent anti-inflammatory macrolactones of the oxacyclododecindione type

2015

An esterification/Friedel-Crafts-cyclization approach permitted the first successful synthetic entry into the oxacyclododecindione subclass of the dihydroxyphenylacetic acid lactone-type natural products. This route allowed the preparation of two highly active anti-inflammatory fungal secondary metabolites 14-deoxyoxacyclododecindione and 14-deoxy-4-dechlorooxacyclododecindione as well as their 14-desmethyl analogues.

Shell/core differences in mu- and delta-opioid receptor modulation of dopamine efflux in nucleus accumbens

2008

The mu- and delta-opioid receptors located at the terminal level in nucleus accumbens are involved in the opiate modulation of dopamine release in this brain area. However, recent studies suggest that the effects of opioid drugs on the core subregion of nucleus accumbens may completely differ from those observed in the shell. We used in vivo microdialysis to simultaneously apply selective mu- and delta-opioid receptor agonists and to measure extracellular levels of dopamine in three subregions of the accumbens, namely shell, core, and the transition zone between them. The regional analysis of these subregions of the accumbens demonstrated that basal levels of dopamine and its metabolites we…

Assessment of the abuse potential of MDMA in the conditioned place preference paradigm: Role of CB1 receptors

2013

Numerous reports have highlighted the role of the endocannabinoid system in the addictive potential of MDMA (3,4-methylenedioxy-methamphetamine). A previous report showed that CB1 knockout (KOCB1) mice do not acquire MDMA self-administration, despite developing conditioned place preference (CPP). This contradiction could be due to the particular procedure of place conditioning used. The present work compares MDMA-induced CPP in KOCB1 mice using unbiased and biased procedures of place conditioning. In the unbiased procedure, MDMA induced CPP and reinstatement of the extinguished preference in wild type (WT) mice, but not in KOCB1 mice. In contrast, in a biased protocol of CPP, MDMA produced …

Influence of the amount of food ingested on mesolimbic dopaminergic system activity: a microdialysis study.

1996

Abstract The mesolimbic dopaminergic system (MDS) has been shown to be activated by ingestive behaviors, and it has been suggested that this activation may be related to the rewarding properties of foods. Because rats eat more when given a more palatable diet, this study was undertaken to determine the relationship between the amount of food ingested and DA release in the nucleus accumbens of freely moving rats. The extracellular levels of dopamine (DA), 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) were measured by high-performance liquid chromatography with electrochemical detection on microdialysis samples from the nucleus accumbens. Each rat underwent three microdia…

Critical role of nitric oxide on nicotine-induced hyperactivation of dopaminergic nigrostriatal system: electrophysiological and neurochemical eviden…

2010

Nicotine, the main psychoactive ingredient in tobacco, stimulates dopamine (DA) function, increasing DA neuronal activity and DA release. DA is involved in both motor control and in the rewarding and reinforcing effects of nicotine; however, the complete understanding of its molecular mechanisms is yet to be attained. Substantial evidence indicates that the reinforcing properties of drugs of abuse, including nicotine, can be affected by the nitric oxide (NO) system, which may act by modulating central dopaminergic function. In this study, using single cell recordings in vivo coupled with microiontophoresis and microdialysis in freely moving animals, the role of NO signaling on the hyperacti…

Adolescent pre-exposure to ethanol or MDMA prolongs the conditioned rewarding effects of MDMA

2011

Adolescents often take ethanol (EtOH) in combination with MDMA (3,4-methylenedioxymethylamphetamine). In the present work we studied the effect of repeated intermittent adolescent pre-exposure to both drugs on the behavioral and neurochemical effects of MDMA in mice. Sixteen days after pre-treatment, the rewarding and reinstating effects of MDMA in the conditioned place preference (CPP) paradigm were evaluated, along with the levels of biogenic amines, basal motor activity and corticosterone response to different challenges. Pre-exposure to EtOH, MDMA or EtOH+MDMA did not affect the CPP induced by 10mg/kg of MDMA. However, adolescent exposure to EtOH or MDMA increased the duration of the co…