Search results for "VITRO"
showing 10 items of 2786 documents
Thymidine analogs are transferred from prelabeled donor to host cells in the central nervous system after transplantation: a word of caution
2006
Thymidine analogs, including bromodeoxyuridine, chlorodeoxyuridine, iododeoxyuridine, and tritiated thymidine, label dividing cells by incorporating into DNA during S phase of cell division and are widely employed to identify cells transplanted into the central nervous system. However, the potential for transfer of thymidine analogs from grafted cells to dividing host cells has not been thoroughly tested. We here demonstrate that graft-derived thymidine analogs can become incorporated into host neural precursors and glia. Large numbers of labeled neurons and glia were found 3-12 weeks after transplantation of thymidine analog-labeled live stem cells, suggesting differentiation of grafted ce…
Pharmacological Suppression of CNS Scarring by Deferoxamine Reduces Lesion Volume and Increases Regeneration in an In Vitro Model for Astroglial-Fibr…
2015
Lesion-induced scarring is a major impediment for regeneration of injured axons in the central nervous system (CNS). The collagen-rich glial-fibrous scar contains numerous axon growth inhibitory factors forming a regeneration-barrier for axons. We demonstrated previously that the combination of the iron chelator 2,2'-bipyridine-5,5'-decarboxylic acid (BPY-DCA) and 8-Br-cyclic AMP (cAMP) inhibits scar formation and collagen deposition, leading to enhanced axon regeneration and partial functional recovery after spinal cord injury. While BPY-DCA is not a clinical drug, the clinically approved iron chelator deferoxamine mesylate (DFO) may be a suitable alternative for anti-scarring treatment (A…
Parallelized TCSPC for dynamic intravital fluorescence lifetime imaging : quantifying neuronal dysfunction in neuroinflammation
2013
Two-photon laser-scanning microscopy has revolutionized our view on vital processes by revealing motility and interaction patterns of various cell subsets in hardly accessible organs (e.g. brain) in living animals. However, current technology is still insufficient to elucidate the mechanisms of organ dysfunction as a prerequisite for developing new therapeutic strategies, since it renders only sparse information about the molecular basis of cellular response within tissues in health and disease. In the context of imaging, Forster resonant energy transfer (FRET) is one of the most adequate tools to probe molecular mechanisms of cell function. As a calibration-free technique, fluorescence lif…
The isolated perfused rat brain as a model for studying drugs acting on the CNS
1974
An isolated perfused brain preparation is regarded as offering some important advantages over intact animals or tissue slices for studying drug effects on the CNS. The rat is by far the most suitable laboratory animal for this technique because of low cost, ease of preparation and extensive literature available for comparative purposes. In this paper various preparation techniques and perfusion systems for an isolated rat brain are reported. Investigations are presented proving the viability of the isolated perfused rat brain for more than seven hours and its suitability for studies on cerebral metabolism. Until now this preparation has been successfully used for pharmacological investigati…
Diffusion in slice preparations bathed in unstirred solutions
1987
A diffusion model is described here, which allows for the estimations of drug concentration changes in porous media, such as in slice tissues of the central nervous system (CNS) bathed in unstirred solutions following abrupt changes of drug concentration. This model may be used for the interpretation of data obtained in neuropharmacological studies if (i) the diffusion coefficient of the molecules under investigation is constant within the excised tissue, (ii) drug molecules are diffusing only in the extracellular space (ECS) and are not bound by the tissue, (iii) drug molecules diffuse mainly within one dimension, (iv) the drug concentration in the bath is changed within 5 s, and (v) the b…
Comparison of the effects of chloral hydrate and trichlorethanol on the EEG of the isolated perfused rat brain.
1973
An isolated perfused rat brain preparation was used to compare the effects of chloral hydrate and its metabolite trichloroethanol on the EEG. The concentrations of chloral hydrate and trichloroethanol in the perfusion medium ranged from 1.5 to 5.5 mM. 5, 10, 15, and 30 min after the beginning of the perfusions EEG-recordings were taken. The recordings were evaluated both by a descriptive method and by a simple quantitative appraoch, counting the waves with an amplitude greater than 50 microvolts and averaging this value for a period of 1 sec. The following results were obtained: Both drugs exhibited CNS depressant activity. Between 5 and 10 min of perfusion the effect of trichloroethanol wa…
Rat CNS cell culture. Enhancement of neuronal survival and delay of glial proliferation by serum from patients with multiple sclerosis. A morphologic…
1984
The addition of serum from multiple sclerosis (MS) patients to the culture medium of dissociated cells from cerebral hemispheres of rat embryos caused a delay in glial proliferation and an enhancement of neuronal survival. Sera from normal individuals and patients with other neurological diseases failed to show this effect. These morphological observations are interpreted as the outcome of inhibition of in vitro gliogenesis.
Binding of flunitrazepam to differentiating neurons cultured in a chemically defined, hormone-supplemented medium
1990
[3H]Flunitrazepam (FNZ) binding to cortical neurons from fetal rat brain was investigated in vitro. The use of a synthetic medium specific for neurons made it possible to plot a developmental curve of3H-FNZ binding in an almost pure neuronal culture. Detectable specific binding was present in vitro at time 0 (that is, the 16th gestational day). A progressive increase of binding, due to an increment in the number of recognition sites, was observed on the subsequent days. The affinity of the specific binding sites to3H-FNZ was enhanced by the addition of exogenous GABA, whereas the density was not affected. © 1990 Plenum Publishing Corporation.
Nicotinic receptor function in the mammalian central nervous system.
1995
The diversity of neuronal nicotinic receptors (nAChRs) in addition to their possible involvement in such pathological conditions as Alzheimer's disease have directed our research towards the characterization of these receptors in various mammalian brain areas. Our studies have relied on electrophysiological, biochemical, and immunofluorescent techniques applied to cultured and acutely dissociated hippocampal neurons, and have been aimed at identifying the various subtypes of nAChRs expressed in the mammalian central nervous system (CNS), at defining the mechanisms by which CNS nAChR activity is modulated, and at determining the ion permeability of CNS nAChR channels. Our findings can be sum…
Clastogenic and aneuploidizing effects of antiblastic busulphan revealed by kinetochore immunofluorescence in CHO cells.
1991
We utilized, in CHO cells, the cytoplasm preservation technique to evaluate the micronucleus frequency at different busulphan concentrations, and the indirect immunofluorescence technique, using sera obtained from patients with scleroderma (CREST variant), to analyze if busulphan-induced micronuclei have kinetochores. Results show that this alkylating agent is capable of causing a significant increase of micronuclei in vitro, a great part (40%) of them having CREST-positive kinetochores. These findings confirm the clastogenic effect of busulphan and reveal a considerable capability of this agent to induce aneuploidy. These results are examined taking into account the high incidence of secon…