Search results for "DIALYSIS"

Serotonin control of central dopaminergic function: focus on in vivo microdialysis studies

2008

In this review, the functional interactions between serotonin (5-HT) and dopamine (DA) neuronal systems are discussed with the focus on microdialysis studies in the rodent brain (mainly rats). 5-HT by itself is involved both directly and indirectly via actions on complex neuronal circuitry, in the regulation of DA release through multiple 5-HT receptors, playing a critical role in the development of normal and abnormal behaviours. Recent evidence suggests that dysfunction of dopaminergic and serotoninergic neurotransmitter systems contributes to various disorders including depression, schizophrenia, Parkinson's disease and drug abuse. Here we summarize recent neurochemical works that have e…

In Vivo Microdialysis in Parkinson’s Research

2009

Parkinson’s disease (PD) is a progressive neurodegenerative disorder that is primarily characterized by the degeneration of dopamine (DA) neurons in the nigrostriatal system, which in turn produces profound neurochemical changes within the basal ganglia, representing the neural substrate for parkinsonian motor symptoms. The pathogenesis of the disease is still not completely understood, but environmental and genetic factors are thought to play important roles. Research into the pathogenesis and the development of new therapeutic intervention strategies that will slow or stop the progression of the disease in human has rapidly advanced by the use of neurotoxins that specifically target DA ne…

Acute Subdural Hematoma in Pigs: Role of Volume on Multiparametric Neuromonitoring and Histology

2008

Traumatic brain injury (TBI) is often complicated by acute subdural hemorrhage (ASDH) with a high mortality rate. The pathophysiological mechanisms behind such an injury type and the contribution of blood to the extent of an injury remain poorly understood. Therefore, the goals of this study were to establish a porcine ASDH model in order to investigate pathomechanisms of ASDH and to compare effects induced by blood or sheer volume. Thus, we infused 2, 5, and 9 mL of blood (up to 15% of intracranial volume), and we compared a 5-mL blood and paraffin oil volume to separate out effects of extravasated blood on brain tissue. An extended neuromonitoring was applied that lasted up to 12 h after …

Quantitative In Vivo Microdialysis in Pharmacokinetic Studies

2012

Dual modulation of striatal acetylcholine release by hyperforin, a constituent of St. John's wort.

2002

Extracts of the medicinal plant St. John's wort (Hypericum perforatum) are widely used for the treatment of mild to moderate depression. Hyperforin, a constituent of St. John's wort, is known to inhibit the sodium-dependent uptake of catecholamines and amino acids into synaptic nerve endings, probably by interference with mechanisms controlling the synaptic sodium concentration. Because de novo synthesis of acetylcholine (ACh) is dependent on sodium-dependent high-affinity choline uptake, we studied the effect of hyperforin on choline (Ch) uptake in vitro and on striatal ACh release in vivo using microdialysis. In rat brain synaptosomes, hyperforin inhibited high-affinity choline uptake wit…

Effect Of Inflammatory Pain On Alcohol-Induced Dopamine Release In The Nucleus Accumbens: Behavioural Implications In Rat Models

2019

AbstractRecent studies have drawn the attention to the link between Alcohol Use Disorder (AUD) and the presence of pain. Indeed, the correct management of pain in patients with a previous history of AUD has been reported to decrease the risk of relapse in alcohol drinking, suggesting that in this prone population, pain may increase the vulnerability to relapse. Previous data in male rats revealed that inflammatory pain desensitizes mu opioid receptors (MORs) in the ventral tegmental area (VTA) and increases intake of high doses of heroine. Due to the relevant role of MORs in alcohol effects, we hypothesize that pain may also alter alcohol reinforcing properties and therefore affect alcohol …

Stimulation of hippocampal acetylcholine release by hyperforin, a constituent of St. John’s Wort

2004

Abstract Extracts of the medicinal plant St. John’s Wort ( Hypericum perforatum ) are widely used in the therapy of affective disorders and have been reported to exert antidepressant, anxiolytic, and cognitive effects in experimental and clinical studies. We here report that hyperforin, the major active constituent of the extract, increases the release of acetylcholine from rat hippocampus in vivo as determined by microdialysis. Hippocampal acetylcholine levels were increased by 50–100% following the systemic administration of pure hyperforin at doses of 1 and 10 mg/kg. The effect was almost completely suppressed by local perfusion with calcium-free buffer or with tetrodotoxin (1 μM). We co…

Nephrogenic systemic fibrosis--a rapidly progressive disabling disease with limited therapeutic options.

2009

Background Nephrogenic systemic fibrosis (NSF) affects some patients on dialysis after gadolinium contrast agent–enhanced magnetic resonance imaging. It is characterized by progressive skin fibrosis of the extremities, sometimes including the trunk and internal organs. Methods The clinical course of 10 patients with biopsy-proven NSF was analyzed retrospectively with regard to gadolinium exposition, disease onset, and progression of NSF with special emphasis on physical mobility and impact of different therapeutic approaches. Results Despite physiotherapy and different additional therapeutic approaches (eg, immunosuppression, ultraviolet A-1 phototherapy, or extracorporal photopheresis) all…

Prevalence of biliary lithiasis in a Sicilian population of chronic renal failure patients.

2003

BACKGROUND The aim of this study was to evaluate the prevalence of biliary lithiasis (BL) and associated risk factors in a population of undialysed patients with chronic renal failure (CRF), and to compare these with findings we had obtained previously in chronic haemodialysis (HD) patients and in subjects from the general population located in the same geographic region. METHODS A total of 118 CRF patients on conservative treatment were included in the study. In all subjects, we measured several clinical and humoral parameters potentially correlated with BL. Liver and biliary tract ultrasonography was performed with a 3.5 MHz linear probe after at least 12 h of fasting. RESULTS The prevale…

A reinforcement learning approach for individualizing erythropoietin dosages in hemodialysis patients

2009

This paper presents a reinforcement learning (RL) approach for anemia management in patients undergoing chronic renal failure. Erythropoietin (EPO) is the treatment of choice for this kind of anemia but it is an expensive drug and with some dangerous side-effects that should be considered especially for patients who do not respond to the treatment. Therefore, an individualized treatment appears to be necessary. RL is a suitable approach to tackle this problem. Moreover, resulting policies are similar to medical protocols, and hence, they can easily be transferred to daily practice. A cohort of 64 patients are included in the study. An implementation of the Q-learning algorithm based on a st…