Effects of dopamine depletion in the medial prefrontal cortex on the stress-induced increase in extracellular dopamine in the nucleus accumbens core and shell
167
Citation
80
Reference
10
Related Paper
Citation Trend
Keywords:
Microdialysis
Dextroamphetamine
Cite
Citations (11)
Neurochemical
Stimulant
Cite
Citations (55)
Caudate nucleus
Conditioned place preference
Cite
Citations (275)
Dextroamphetamine
Cite
Citations (29)
Strong evidence supports a central role for beta-amyloid protein (Aß) in the pathogenesis of Alzheimer's disease (AD). Much attention has been focused on toxic forms of soluble and insoluble Aß. Gaining an understanding of the soluble species of Aß that are released from neurons may provide greater insight into the pathophysiology of AD. Previous work has demonstrated the ability to measure extracellular concentrations of soluble Aß in the brains of freely moving animals using in vivo microdialysis (Cirrito et al., 2003). We have compared two distinct microdialysis methods, conventional microdialysis and push-pull microdialysis, to monitor Aß levels in the brain interstitial fluid (ISF) of AD transgenic animals. In addition, we examined the effects of gamma secretase inhibition with ELN44989 on the levels of Aß (1-x) and Aß (1-40). Conventional microdialysis is limited by the membrane cut-off size and generally allows measurement of molecules smaller than 30-60 KDa. Conversely, push-pull microdialysis allows for detection of molecules up to 1-3 MDa offering the advantage of detecting a broader range of soluble oligomeric Aß species. Both methods were employed in this study, followed by ELISA measurement of Aß (1-x) and Aß (1-40). Aß (1-x) and Aß (1-40) in dialysates from conventional microdialysis were 243 pg/ml and 125 pg/ml, respectively. Using push pull microdialysis, levels of Aß (1-x) and Aß (1-40) were notably higher. In both cases, ISF Aß levels were significantly reduced following systemic administration of ELN44989. We conclude that push-pull microdialysis provides distinct advantages over conventional microdialysis for the detection of Aß species in the rodent brain, and can provide greater insight into role of multiple Abeta species (including high molecular weight) to pathological and functional endpoints.
Microdialysis
Interstitial fluid
Pathophysiology
Amyloid beta
Cite
Citations (0)
Microdialysis
Neurochemical
Cite
Citations (46)
Cite
Citations (294)
Microdialysis technique has been developed to study secretory function of the adrenal gland in anesthesized rats. Concentration of adrenaline and noradrenaline in sequential 20 min microdialysis samples was measured by HPLC with electrochemical detection. The suitability of method was tested by local and central stimulation of catecholamine secretion. In the first case 100 mmol of KCl or 1 mmol of carbachol were added to perfusion medium, in the second one hypovolemic hypotension was applied. All the stimuli used increased catecholamine levels in the adrenal gland dialysates. Institute of Experimental Cardiology of the All-Union.
Microdialysis
Cite
Citations (4)
The microdialysis technique can be used to get dialysates of the subcutaneous tissue, which can be continuously measured by an amperometric glucose sensor. In order to get further insight into the microdialysis procedure, we used a steady-state theory for microdialysis to predict the recovery of glucose in the dialysate and compared the results to experimental data obtained by a combination of the microdialysis technique with continuous amperometric glucose sensing. The recovery of glucose obtained in vitro for two different microdialysis probes was close to the theoretical predictions. When quantifying the predictions of the model with regard to the spatial concentration profile in the subcutaneous tissue, it appeared, that the presence of the microdialysis probe depressed the concentration of glucose for 0.2 mm from the probe surface. In a 24 hour in vivo experiment, there were less fluctuations in the sensor signal when the patient was lying in bed compared to the time, when the patient could move freely. In conclusion, the combination of microdialysis and glucose sensor seems to be a promising approach to a continuously functioning glucose sensing system. However, the microdialysis procedure itself disturbs the surrounding of the probe leading to a concentration gradient of glucose. This might explain some differences between the course of blood glucose and the course of subcutaneous glucose, measured by the combination of microdialysis and an amperometric glucose sensor. Further developments of such systems should aim at implanting microdialysis devices which have a minimal influence upon the tissue metabolism.
Microdialysis
Amperometry
Subcutaneous tissue
Cite
Citations (23)