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Francisco Silveira Guimarães - One of the best experts on this subject based on the ideXlab platform.
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modulation of anxiety like behaviour by transient receptor potential vanilloid type 1 trpv1 channels located in the dorsolateral periaqueductal gray
European Neuropsychopharmacology, 2009Co-Authors: Ana Luisa B Terzian, Francisco Silveira Guimarães, Daniele C Aguiar, Fabricio A MoreiraAbstract:The endocannabinoid anandamide is a possible agonist at the Transient Receptor Potential Vanilloid Type 1 (TRPV1) channel, in addition to its agonist activity at cannabinoid type 1 (CB1) receptor. In the midbrain dorsolateral periaqueductal gray (dlPAG) our previous data showed that CB1 activation induces anxiolytic-like effects. However, the role of TRPV1 has remained unclear. Thus, in the present study we Tested the hypothesis that this channel would contribute to the modulation of anxiety-like behaviour in the dlPAG. Male Wistar rats received local injections of the TRPV1 antagonist capsazepine (10-60 nmol) and were submitted to the elevated plus-maze (EPM) and to the Vogel Test. In addition, animals received local injections of capsaicin (0.01-1 nmol), a TRPV1 agonist, and were Tested in the same models. In accordance with our hypothesis, capsazepine produced anxiolytic-like effects both in the EPM and in the Vogel Test. Capsaicin mimicked these results, which might be attributed to its ability to quickly desensitize the channel. Altogether, our data suggest that, while CB1 receptors seem to inhibit aversive responses in the dlPAG, TRPV1 could facilitate them. Thus, CB1 and TRPV1 may have opposite functions in modulating anxiety-like behaviour in this region.
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anxiolytic like effect of cannabidiol in the rat Vogel conflict Test
Progress in Neuro-psychopharmacology & Biological Psychiatry, 2006Co-Authors: Fabricio A Moreira, Daniele C Aguiar, Francisco Silveira GuimarãesAbstract:Cannabidiol (CBD) is a major constituent of the Cannabis sativa plant. It inhibits the anxiogenic activity of high doses of Delta9-tetrahydrocannabinol and induces anxiolytic-like effects. However, the mechanisms underlying the actions of CBD are unknown. Therefore, the aim of the present study was to Test the effects of CBD in the Vogel Test, a widely used animal model of anxiety. In addition, it was verified if these effects would depend on benzodiazepine-receptor activation. After 24 h of water deprivation, male Wistar rats were subjected to an initial 3-min non-punished (pre-Test) drinking session. This was followed by an additional 24-h period of water deprivation followed by a 3-min punished-licking session (Test). Diazepam (3 mg/kg) or CBD (2.5, 5 or 10 mg/kg) were intraperitoneally injected 30 min before the Test session. CBD (10 mg/kg) and diazepam had similar anticonflict effects, increasing the number of punished licks. The effect of diazepam, but not of CBD, was prevented by the benzodiazepine-receptor antagonist flumazenil (10 mg/kg). To exclude that the anticonflict effects were reflecting non-specific drug effects, we checked the effects of CBD on water consumption and nociceptive response. The drug did not interfere on the former variable in a non-punished Test session. Moreover, contrary to morphine (5 mg/kg), CBD was ineffective in the tail-flick Test. In conclusion, CBD induced an anticonflict effect not mediated by benzodiazepine receptors or by non-specific drug interference on nociceptive threshold or water consumption. These results reinforce the hypothesis that this cannabinoid has anxiolytic properties.
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Role of glutamate ionotropic receptors in the dorsomedial hypothalamic nucleus on anxiety and locomotor behavior.
Pharmacology biochemistry and behavior, 2004Co-Authors: M.c. Jardim, Francisco Silveira GuimarãesAbstract:The medial hypothalamus is proposed to play an important role in the modulation of defensive responses. Administration of a NMDA receptor antagonist (AP7) into the dorsomedial hypothalamic nucleus (DMH) of rats reduced exploratory behavior in the open field and elevated plus-maze (EPM), but failed to produce anxiolytic effects in the latter Test. The objectives of the present work were to Test the hypotheses that (i) AP7 injections into the DMH would also fail to induce anxiolytic effects in another model of anxiety, the Vogel's punished licking Test; (ii) injection into the DMH of other glutamate ionotropic antagonists would also decreased exploratory behavior; and (iii) the decrease in exploratory activity found after AP7 administration into the DMH does not involve any gross locomotor impairment. Male Wistar rats (n=5-16/group) with cannulas aimed at the DMH were submitted to the following behavioral Tests: EPM, Vogel, catalepsy and rota-rod. Diazepam (3 mg/kg) and haloperidol (2.5 mg/kg) were used as positive controls in the Vogel, rota-rod and catalepsy Tests. AP7 failed to modify the number of punished licks in the Vogel Test. It also did not induce any change on the rota-rod and catalepsy Tests. Diazepam increased the number of punished licks and reduced the latency to fall in the rota-rod. Both 7-chlorokynurenic acid (4-8 nmol), an antagonist of the glycine competitive site in the NMDA receptor and 2,3-dioxo-6-nitro-1,2,3,4-tetrahydrobenzo-[f]-quinoxaline-7-sulphonamide (NBQX, 1-10 nmol), a non-NMDA receptor antagonist, decreased the total distance moved in the EPM. The former compound also decreased open arm exploration at the dose of 4 nmol. The results suggest that the antagonism of ionotropic glutamate receptors in the DMH does not induce anxiolytic effects in the EPM or Vogel Tests, but decreases exploratory behavior in a new environment.
Andrzej Pilc - One of the best experts on this subject based on the ideXlab platform.
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the group iii mglu receptor agonist acpt i exerts anxiolytic like but not antidepressant like effects mediated by the serotonergic and gaba ergic systems
Neuropharmacology, 2009Co-Authors: Katarzyna Stachowicz, Andrzej Pilc, A Klodzinska, Agnieszka Paluchaponiewiera, Stephan Schann, Pascal NeuvilleAbstract:Abstract Our earlier studies have demonstrated that (1S,3R,4S)-1-aminocyclo-pentane-1,3,4-tricarboxylic acid ACPT-I, a group III mGlu receptor agonist, produced anxiolytic-like and antidepressant-like actions after central administration. Here we describe the anxiolytic-like effects of ACPT-I after intraperitoneal administration in the stress-induced hyperthermia (SIH), elevated plus-maze (PMT) Tests in mice and in the Vogel Test in rats. However, the compound did not produce antidepressant-like effects in the tail suspension Test (TST) or in the forced swim Test (FST) in mice. The potential anxiolytic effect of ACPT-I (20 mg/kg) in the SIH Test was inhibited by the benzodiazepine receptor antagonist flumazenil (given i.p., 10 mg/kg), and by a 5-HT1A receptor antagonist N-{2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl}-N-(2-pyridynyl) cyclohexane-carboxamide (WAY100635) (0.1 mg/kg s.c.). At the same time, ritanserin (0.5 mg/kg i.p.), the 5-HT2A/C receptor antagonist, did not change the anxiolytic-like effects of ACPT-I. The results of these studies indicate that the GABA-ergic and serotonergic systems are involved in the potential anxiolytic action of ACPT-I.
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anxiolytic like action of mtep expressed in the conflict drinking Vogel Test in rats is serotonin dependent
Neuropharmacology, 2007Co-Authors: Katarzyna Stachowicz, Gabriel Nowak, Andrzej Pilc, Krystyna Golembiowska, Magdalena Sowa, E ChojnackawojcikAbstract:Abstract The purpose of the present study was to investigate whether the anxiolytic-like action of a selective and brain penetrable group I metabotropic glutamate (mGlu5) receptor antagonist 3-[(2-methyl-1,3-tiazol-4-yl)ethynyl]-pyridine (MTEP) is dependent upon the serotonergic system. Experiments were performed on male Wistar rats. The Vogel conflict drinking Test was used to detect anxiolytic-like activity. MTEP administered intraperitoneally at doses of 1, 3 and 6 mg/kg induced anxiolytic-like effect. The potential anxiolytic effect of MTEP (1 mg/kg) was inhibited by a nonselective 5-HT receptor antagonist metergoline (2 mg/kg i.p.) and 5-HT2A/2C receptor antagonist ritanserin (0.5 mg/kg i.p.), but not by a 5-HT1A receptor antagonist N-{2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl}-N-(2-pyridynyl)cyclohexane-carboxamide (WAY 100635) (0.1 mg/kg i.p). The anxiolytic effect of MTEP (6 mg/kg) was attenuated by ritanserin (1 mg/kg i.p.). Moreover, MTEP-induced a dose-dependent release of serotonin in the frontal cortex. The obtained results suggest that the potential anxiolytic effect of the mGlu5 receptor antagonist MTEP is due to the increased serotonin release with subsequent activation of 5-HT2A/2C receptors, most probably located postsynaptically, but not by the 5-HT1A receptors.
Fabricio A Moreira - One of the best experts on this subject based on the ideXlab platform.
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modulation of anxiety like behaviour by transient receptor potential vanilloid type 1 trpv1 channels located in the dorsolateral periaqueductal gray
European Neuropsychopharmacology, 2009Co-Authors: Ana Luisa B Terzian, Francisco Silveira Guimarães, Daniele C Aguiar, Fabricio A MoreiraAbstract:The endocannabinoid anandamide is a possible agonist at the Transient Receptor Potential Vanilloid Type 1 (TRPV1) channel, in addition to its agonist activity at cannabinoid type 1 (CB1) receptor. In the midbrain dorsolateral periaqueductal gray (dlPAG) our previous data showed that CB1 activation induces anxiolytic-like effects. However, the role of TRPV1 has remained unclear. Thus, in the present study we Tested the hypothesis that this channel would contribute to the modulation of anxiety-like behaviour in the dlPAG. Male Wistar rats received local injections of the TRPV1 antagonist capsazepine (10-60 nmol) and were submitted to the elevated plus-maze (EPM) and to the Vogel Test. In addition, animals received local injections of capsaicin (0.01-1 nmol), a TRPV1 agonist, and were Tested in the same models. In accordance with our hypothesis, capsazepine produced anxiolytic-like effects both in the EPM and in the Vogel Test. Capsaicin mimicked these results, which might be attributed to its ability to quickly desensitize the channel. Altogether, our data suggest that, while CB1 receptors seem to inhibit aversive responses in the dlPAG, TRPV1 could facilitate them. Thus, CB1 and TRPV1 may have opposite functions in modulating anxiety-like behaviour in this region.
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anxiolytic like effect of cannabidiol in the rat Vogel conflict Test
Progress in Neuro-psychopharmacology & Biological Psychiatry, 2006Co-Authors: Fabricio A Moreira, Daniele C Aguiar, Francisco Silveira GuimarãesAbstract:Cannabidiol (CBD) is a major constituent of the Cannabis sativa plant. It inhibits the anxiogenic activity of high doses of Delta9-tetrahydrocannabinol and induces anxiolytic-like effects. However, the mechanisms underlying the actions of CBD are unknown. Therefore, the aim of the present study was to Test the effects of CBD in the Vogel Test, a widely used animal model of anxiety. In addition, it was verified if these effects would depend on benzodiazepine-receptor activation. After 24 h of water deprivation, male Wistar rats were subjected to an initial 3-min non-punished (pre-Test) drinking session. This was followed by an additional 24-h period of water deprivation followed by a 3-min punished-licking session (Test). Diazepam (3 mg/kg) or CBD (2.5, 5 or 10 mg/kg) were intraperitoneally injected 30 min before the Test session. CBD (10 mg/kg) and diazepam had similar anticonflict effects, increasing the number of punished licks. The effect of diazepam, but not of CBD, was prevented by the benzodiazepine-receptor antagonist flumazenil (10 mg/kg). To exclude that the anticonflict effects were reflecting non-specific drug effects, we checked the effects of CBD on water consumption and nociceptive response. The drug did not interfere on the former variable in a non-punished Test session. Moreover, contrary to morphine (5 mg/kg), CBD was ineffective in the tail-flick Test. In conclusion, CBD induced an anticonflict effect not mediated by benzodiazepine receptors or by non-specific drug interference on nociceptive threshold or water consumption. These results reinforce the hypothesis that this cannabinoid has anxiolytic properties.
Adam Plaźnik - One of the best experts on this subject based on the ideXlab platform.
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the influence of serotonin depletion on rat behavior in the Vogel Test and brain 3h zolpidem binding
Journal of Neural Transmission, 1999Co-Authors: M Nazar, Marek Siemiątkowski, Andrzej Bidzinski, A Czlonkowska, Halina Sienkiewiczjarosz, Adam PlaźnikAbstract:The influence of p-chlorophenylalanine (p-CPA) and 5,7-dihydroxytryptamine (5,7-DHT)-induced serotonin depletion on rat behavior as well as on zolpidem's the behavioral effects and binding to some brain areas of zolpidem, was examined with the help of Vogel's punished drinking Test and autoradiography, respectively. Moreover, changes in the serotonin levels and turnover rate were studied in the forebrain and brainstem of rats pretreated with various ligands at the benzodiazepine (BDZ) receptors (midazolam, bretazenil, abecarnil, zolpidem). These drugs were given at doses shown previously to significantly disinhibit animal behavior suppressed by punishment in the Vogel Test (Nazar et al., 1997). It was found that serotonin decrease in the frontal cortex and hippocampus after p-CPA significantly and inversely correlated with rat behavior controlled by fear in the VT. p-CPA produced an anticonflict activity in the absence of effect on spontaneous drinking, pain threshold and motility of animals. All applied benzodiazepine receptor ligands decreased the 5-HT turnover rate in the frontal cortex and hippocampus, whereas in the brainstem only abecarnil and zolpidem diminished 5-hydroxyindoleacetic acid levels. This part of the study replicated earlier data with neurotoxins and indicated that the anxiolytic-like effect of 5-HT depletion in some models of anxiety did not depend on changes in animal appetitive behavior or stimulus control. Moreover, the fact that all non-selective and selective (zolpidem) agonists of the type 1 benzodiazepine receptors seemed to produce the same anticonflict effect and decreasing 5-HT turnover indicates that this subtype of benzodiazepine receptor may be important for the interaction between brain 5-HT and GABA/BDZ systems. Accordingly, it was found that serotonin decrease enhanced the anticonflict effect of zolpidem in the Vogel Test and increased 3H-zolpidem binding to the occipital cortex and substantia nigra. Altogether, the present study provides more arguments for the role of changes in the activity of brain 5-HT innervation in the control of emotional processes. Moreover, it points to the BDZ1 receptor subtype as a possible target of interaction between brain 5-HT and GABAA/BDZ systems.
Daniele C Aguiar - One of the best experts on this subject based on the ideXlab platform.
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modulation of anxiety like behaviour by transient receptor potential vanilloid type 1 trpv1 channels located in the dorsolateral periaqueductal gray
European Neuropsychopharmacology, 2009Co-Authors: Ana Luisa B Terzian, Francisco Silveira Guimarães, Daniele C Aguiar, Fabricio A MoreiraAbstract:The endocannabinoid anandamide is a possible agonist at the Transient Receptor Potential Vanilloid Type 1 (TRPV1) channel, in addition to its agonist activity at cannabinoid type 1 (CB1) receptor. In the midbrain dorsolateral periaqueductal gray (dlPAG) our previous data showed that CB1 activation induces anxiolytic-like effects. However, the role of TRPV1 has remained unclear. Thus, in the present study we Tested the hypothesis that this channel would contribute to the modulation of anxiety-like behaviour in the dlPAG. Male Wistar rats received local injections of the TRPV1 antagonist capsazepine (10-60 nmol) and were submitted to the elevated plus-maze (EPM) and to the Vogel Test. In addition, animals received local injections of capsaicin (0.01-1 nmol), a TRPV1 agonist, and were Tested in the same models. In accordance with our hypothesis, capsazepine produced anxiolytic-like effects both in the EPM and in the Vogel Test. Capsaicin mimicked these results, which might be attributed to its ability to quickly desensitize the channel. Altogether, our data suggest that, while CB1 receptors seem to inhibit aversive responses in the dlPAG, TRPV1 could facilitate them. Thus, CB1 and TRPV1 may have opposite functions in modulating anxiety-like behaviour in this region.
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anxiolytic like effect of cannabidiol in the rat Vogel conflict Test
Progress in Neuro-psychopharmacology & Biological Psychiatry, 2006Co-Authors: Fabricio A Moreira, Daniele C Aguiar, Francisco Silveira GuimarãesAbstract:Cannabidiol (CBD) is a major constituent of the Cannabis sativa plant. It inhibits the anxiogenic activity of high doses of Delta9-tetrahydrocannabinol and induces anxiolytic-like effects. However, the mechanisms underlying the actions of CBD are unknown. Therefore, the aim of the present study was to Test the effects of CBD in the Vogel Test, a widely used animal model of anxiety. In addition, it was verified if these effects would depend on benzodiazepine-receptor activation. After 24 h of water deprivation, male Wistar rats were subjected to an initial 3-min non-punished (pre-Test) drinking session. This was followed by an additional 24-h period of water deprivation followed by a 3-min punished-licking session (Test). Diazepam (3 mg/kg) or CBD (2.5, 5 or 10 mg/kg) were intraperitoneally injected 30 min before the Test session. CBD (10 mg/kg) and diazepam had similar anticonflict effects, increasing the number of punished licks. The effect of diazepam, but not of CBD, was prevented by the benzodiazepine-receptor antagonist flumazenil (10 mg/kg). To exclude that the anticonflict effects were reflecting non-specific drug effects, we checked the effects of CBD on water consumption and nociceptive response. The drug did not interfere on the former variable in a non-punished Test session. Moreover, contrary to morphine (5 mg/kg), CBD was ineffective in the tail-flick Test. In conclusion, CBD induced an anticonflict effect not mediated by benzodiazepine receptors or by non-specific drug interference on nociceptive threshold or water consumption. These results reinforce the hypothesis that this cannabinoid has anxiolytic properties.
