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Monoamine Systems (monoamine + system)

Distribution by Scientific Domains

Medical Sciences	75%

Selected Abstracts

Pharmacological principles of antidepressant efficacy

HUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue S1 2002
Alan F. Schatzberg
Abstract Both noradrenaline (NA) and serotonin (5-HT) appear to be involved in depression. Evidence suggests that dual-acting antidepressants, i.e. those that affect both monoamine systems, such as tricyclic antidepressants and the noradrenergic and specific serotonergic antidepressant mirtazapine, may have greater efficacy and a faster onset of action than drugs that act on a single monoamine system only, such as the selective serotonin reuptake inhibitors (SSRIs). Cell firing is reduced by SSRIs in the short-term, but is increased by mirtazapine, probably due to its actions on both NA (via ,2 antagonism) and 5-HT (via ,1 -stimulation by NA). This may help to explain clinical evidence suggesting that mirtazapine has a faster onset of action than the more selective antidepressants. Copyright © 2002 John Wiley & Sons, Ltd. [source]

Evidence that serotonin reuptake modulators increase the density of serotonin innervation in the forebrain

JOURNAL OF NEUROCHEMISTRY, Issue 2 2006
Lijun Zhou
Abstract The mechanism of action of commonly used antidepressants remains an issue of debate. In the experiments reported here we studied the effects of three representative compounds, the selective serotonin reuptake inhibitor fluoxetine, the selective serotonin reuptake enhancer tianeptine and the selective norepinephrine reuptake inhibitor desipramine on the structure of central serotonin pathways after a 4-week administration. We found that the serotonin modulators fluoxetine and tianeptine, but not desipramine, increase the density of 5-HT and serotonin transporter (SERT)-immunoreactive axons in the neocortical layer IV and certain forebrain limbic areas, such as piriform cortex and the shell region of nucleus accumbens. These changes were noted in the absence of a significant effect of serotonin antidepressants on the expression of tryptophan hydroxylase (TPH-2), i.e. the rate-limiting enzyme for 5-HT biosynthesis and of SERT at the mRNA level. In addition, we found that anterogradely filled terminal axons from injections of biotinylated dextran amine into the dorsal raphe showed significantly more branching in animals treated with fluoxetine compared with animals treated with liposyn vehicle. Our findings suggest that antidepressants may exert very selective structural effects on their cognate monoamine systems in normal animals and raise the possibility that neurotrophic mechanisms may play a role in their clinical efficacy. [source]

Relationship between saliva level of 3-methoxy-4-hydroxyphenylglycol and mental health in the elderly general population

PSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 5 2008
Guang Y. Li pgs
Aims:, A large number of studies on the monoamine systems in Alzheimer's disease (AD) have found abnormalities of the noradrenergic system in the brain, but there has been no report concerning the relationship between noradrenergic activity and cognitive function in elderly living in a community. The aim of the present study was to explore the relationship between saliva level of 3-methoxy-4-hydroxyphenylglycol (sMHPG) and mental health in this population. Methods:, The study was to examine the relationship between sMHPG and performance on the Mini-Mental State Examination (MMSE), Frontal Assessment Battery (FAB), and Beck Depression Inventory (BDI) in 213 elderly people living in the local community. Results:, sMHPG in female subjects was positively correlated with age (r = 0.24, P = 0.003) and negatively correlated with scores on the MMSE (r = ,0.26, P = 0.0016) and FAB (r = ,0.19, P = 0.024), even after controlling for the effect of age (MMSE r = ,0.20, P = 0.013). Notably, sMHPG was correlated with the pentagon drawing score (P = 0.0008) of MMSE. sMHPG was significantly correlated with BDI score in male subjects, but negatively correlated in female subjects. A gender difference was found in the relationship between the sMHPG and BDI score. Conclusion:, The measurement of sMHPG may be a useful marker of mental health in elderly community-dwelling subjects. [source]

ORIGINAL RESEARCH,BASIC SCIENCE: Acute and Repeated Flibanserin Administration in Female Rats Modulates Monoamines Differentially Across Brain Areas: A Microdialysis Study

THE JOURNAL OF SEXUAL MEDICINE, Issue 5 2010
Kelly A. Allers PhD
ABSTRACT Introduction., Hypoactive sexual desire disorder (HSDD) is defined as persistent lack of sexual fantasies or desire marked by distress. With a prevalence of 10% it is the most common form of female sexual dysfunction. Recently, the serotonin-1A (5-HT1A) receptor agonist and the serotonin-2A (5-HT2A) receptor antagonist flibanserin were shown to be safe and efficacious in premenopausal women suffering from HSDD in phase III clinical trials. Aim., The current study aims to assess the effect of flibanserin on neurotransmitters serotonin (5-HT), norepinephrine (NE), dopamine (DA), glutamate, and ,-aminobutyric acid (GABA) in brain areas associated with sexual behavior. Methods., Flibanserin was administered to female Wistar rats (280,350 g). Microdialysis probes were stereotactically inserted into the mPFC, NAC, or MPOA, under isoflurane anesthesia. The extracellular levels of neurotransmitters were assessed in freely moving animals, 24 hours after the surgery. Main Outcome Measures., Dialysate levels of DA, NE, and serotonin from medial prefrontal cortex (mPFC), nucleus accumbens (NAC), and hypothalamic medial preoptic area (MPOA) from female rats. Results., Acute flibanserin administration decreased 5-HT and increased NE levels in all tested areas. DA was increased in mPFC and MPOA, but not in the NAC. Basal levels of NE in mPFC and NAC and of DA in mPFC were increased upon repeated flibanserin administration, when compared to vehicle-treated animals. The basal levels of 5-HT were not altered by repeated flibanserin administration, but basal DA and NE levels were increased in the mPFC. Glutamate and GABA levels remained unchanged following either repeated or acute flibanserin treatment. Conclusions., Systemic administration of flibanserin to female rats differentially affects the monoamine systems of the brain. This may be the mechanistic underpinning of flibanserin's therapeutic efficacy in HSDD, as sexual behavior is controlled by an intricate interplay between stimulatory (catecholaminergic) and inhibitory (serotonergic) systems. Allers KA, Dremencov E, Ceci A, Flik G, Ferger B, Cremers TIFH, Ittrich C, and Sommer B. Acute and repeated flibanserin administration in female rats modulates monoamines differentially across brain areas: A microdialysis study. J Sex Med 2010;7:1757,1767. [source]