Search results for "Wistar"
showing 10 items of 1094 documents
Behavioral deficits induced by lead exposure are accompanied by serotonergic and cholinergic alterations in the prefrontal cortex
2013
The effects of long-term lead (Pb) exposure producing a blood Pb concentration of lower than 20 μg/dL, i.e. below that associated with overt neurological deficits in occupationally exposed individuals, was studied in adult rats. In order to assess gender differences, we performed parallel behavioral experiments in male and female rats. Exposure to Pb acetate (50 ppm in drinking water) for 6 months induced motor and cognitive alterations, however these effects were gender- and task-dependent. Chronic lead exposure impaired spatial learning assessed in the Morris water maze test (MWM) in both genders, whereas it only induced hyperactivity in the open field and impaired motor coordination in t…
Histamine and serotonin released from the rat perfused heart by compound 48/80 or by allergen challenge influence noradrenaline or acetylcholine exoc…
1994
Terminal nerve fibres of the autonomic nervous system closely approach mast cells in peripheral organs, and mutual influences between release of neurotransmitters or mast cell mediators may cause neuro-immunological interactions. We have studied the influence of mast cell degranulation on the release of endogenous noradrenaline and newly incorporated acetylcholine (such as 14C-choline/acetylcholine overflow) evoked by stimulation of extrinsic postganglionic sympathetic or preganglionic vagal nerves in the rat Langendorff heart perfused with Tyrode solution. Compound 48/80 perfused in normal hearts, or ovalbumin infused into hearts from rats sensitized to ovalbumin, enhanced the overflow of …
The effects of nitric oxide on striatal serotoninergic transmission involve multiple targets: an in vivo microdialysis study in the awake rat
2004
Abstract The role of endogenous nitric oxide (NO) in N -methyl- d -aspartate (NMDA)-induced modulation of serotonin (5-HT) release in the striatum of freely moving rats has been studied using microdialysis technique. NMDA-induced increase in 5-HT release was significantly inhibited by selective nitric oxide synthase (nNOS) inhibitor S -methylthiocitrulline (S-Me-TC), ONOO − scavenger l -cysteine ( l -cys), and guanylate cyclase (GC) inhibitor 1 H [1,2,4]oxadiazolo[4,3- a ]quinoxalin-1-one (ODQ). These data suggest that modulation of 5-HT levels is linked to the formation of NO produced by NMDA receptor activation and that endogenously produced NO increases 5-HT concentrations both by stimul…
Participation of Intracellular Calcium Stores in Serotonin-Induced Contractions in Rat Aorta
1993
Serotonin 1 mumol/l induces a contractile response in the isolated rat aorta in both the presence or absence of extracellular Ca. The present study analyzes the influence of temperature and caffeine on subsequent serotonin-induced contractions. In Ca-free medium, the contraction elicited by serotonin was higher at 25 degrees C than at 37 degrees C. In addition, the existence of two independent intracellular Ca pools releasable by serotonin, one of them also sensitive to caffeine, is postulated. The results also showed that addition of serotonin decreases the contractile response to this agonist in Ca-free medium.
Amplifying effect of serotonin on contractile responses in rat aorta and depletion of intracellular Ca-stores
1993
1. Serotonin, 1 microM, induces a contractile response in isolated rat aorta in the presence or absence of extracellular Ca. 2. In Ca-free media, the fast phasic contraction is lower in magnitude and further addition of serotonin evokes no response. 3. Recovery of the contractile response in Ca-free medium is obtained by a 40 min incubation in Ca-containing solution. 4. In Ca, Mg-free medium, the response to serotonin is significantly higher than that obtained in the presence of Mg. 5. An amplifying effect of serotonin on the contractile responses induced by serotonin itself or by noradrenaline was observed in Ca-containing but not in Ca-free solution.
Presynaptic effects of anandamide and WIN55,212-2 on glutamatergic nerve endings isolated from rat hippocampus
2006
We examined the effects of the endocannabinoide-anandamide (AEA), the synthetic cannabinoid, WIN55,212-2, and the active phorbol ester, 4-beta-phorbol 12-myristate 13-acetate (4-beta-PMA), on the release of [(3)H]d-Aspartate ([(3)H]d-ASP) from rat hippocampal synaptosomes. Release was evoked with three different stimuli: (1) KCl-induced membrane depolarization, which activates voltage-dependent Ca(2+) channels and causes limited neurotransmitter exocytosis, presumably from ready-releasable vesicles docked in the active zone; (2) exposure to the Ca(2+) ionophore-A23187, which causes more extensive transmitter release, presumably from intracellular reserve vesicles; and (3) K(+) channel block…
Effects of the benzodiazepine inverse agonist FG7142 on the structure of anxiety-related behavior of male Wistar rats tested in hole board
2016
Little is known about the structural characteristics of the behavior of rats with enhanced anxiety level. To fill this gap, a study was undertaken where effects of an anxiogenic drug were examined on behavioral structure of rats tested in hole board.This study investigates effects of increased anxiety level on the structure of the behavior of rats tested in hole board METHODS: Different doses of FG7142 (1, 4, 8 mg/kg IP), a potent anxiety-inducing drug, were administered to three groups of male Wistar rats. A further group was administered saline. Experiments were recorded through a digital camera. Quantitative and multivariate approaches were applied.Percent distributions and durations sho…
Validation of a modified model of TNBS-induced colitis in rats. How to induce a chemical colitis in rats
2014
Background: there are no standard practice in the induction of colitis by 2,4,6-trinitrobenzene sulfonic (TNBS) acid. Usually, the repeated administration of TNBS is preferred, because it will result in a local Th1 response that has the characteristics of Crohn's disease. material and Methods: A total of 30 rats were randomized into two groups, consisting of a saline control group of ten rats and a TNBS groups of 20 rats. After the animals were anesthesized, 0,5 ml of either 0,9 % saline 8controls) or TNBS 50 mg/Kg dissolved in 50% ethanol were instilled into the colon through a rubber catheter. The experiment was repeated weekly for four weeks, then, the rats were killed at day 40, and the…
Wistar rat skin as surrogate for human skin in nortriptyline hydrochloride patch studies
2009
Six different matrices were prepared containing nortriptyline hydrochloride (NTH) with hydroxypropyl-methyl-cellulose as polymer. A mixture of transdermal enhancers was included as part of the vehicle. Diffusion studies were carried out through Wistar rat full thickness skin using Franz cells. They were compared with previously determined human heat separated epidermis in order to test if this animal can be used as model for in vivo assays. A linear correlation was obtained between NTH diffusion coefficients through both skin types (r2=0.996).
Characteristics of l-carnitine import into heart cells
2007
Abstract l -carnitine is an essential cofactor for the transport of fatty acids across the mitochondrial membranes. l -carnitine can be provided by food products or biosynthesized in the liver. After intestinal absorption or hepatic biosynthesis, l -carnitine is transferred to organs whose metabolism is dependent upon fatty acid oxidation, such as the skeletal muscle and the heart. The intracellular transport of l -carnitine into the cell requires specific transporters and today, several of these have been characterized. Most of them belong to the solute carrier family. Heart is one of the major target for carnitine transport and use, however basic properties of carnitine uptake by heart ce…