Activation of GABAA receptors in the medial prefrontal cortex produces an anxiolytic-like response

ObjectivesThere has been increasing evidence that the γ-aminobutyric acid (GABA)ergic system is involved in the neurobiology of anxiety. The present study aimed to investigate the role of GABAergic systems in the modulation of anxiety in the medial prefrontal cortex (mPFC) of rats using the elevated plus maze test.MethodsRats were anaesthetised with a mixture of ketamine and xylazine, and then special cannulae were inserted stereotaxically into the mPFC. After 5–7 days of recovery, the effects of intra-mPFC administration of GABAergic agents were studied.ResultsBilateral injection of the GABAA receptor agonist muscimol (0.25, 0.5 and 1 μg/rat) produces an anxiolytic-like effect, shown by significant increases in the percentage of open-arm time (%OAT) and percentage of open-arm entries (%OAE). Intra-mPFC administration of the GABAA receptor antagonist bicuculline (0.25, 0.5 and 1 μg/rat) produces significant anxiogenic-like behaviour. However, intra-mPFC injection of the GABAB receptor agonist baclofen (0.05, 0.1 and 0.2 μg/rat) and the GABAB receptor antagonist CGP35348 (5, 10 and 15 μg/rat) did not alter %OAT and %OAE significantly.ConclusionThe results of the present study demonstrate that the GABAergic system of the mPFC modulates anxiety-related behaviours of rats through GABAA receptors.

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P.4.b.008 Effect of cannabinoid CB1 receptor agonist WIN 55,212-2 in the elevated plus maze test: role of the serotonergic system

European Neuropsychopharmacology ◽

10.1016/s0924-977x(06)70611-3 ◽

2006 ◽

Vol 16 ◽

pp. S464

Author(s):

P. Fadda ◽

M. Scherma ◽

P. Salis ◽

P. Mascia ◽

L. Fattore ◽

...

Keyword(s):

Receptor Agonist ◽

Elevated Plus Maze ◽

Cb1 Receptor ◽

Serotonergic System ◽

Cannabinoid Cb1 Receptor ◽

Elevated Plus Maze Test ◽

Maze Test ◽

Plus Maze

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Anticonvulsant, Anxiolytic and Antidepressant Properties of the β-caryophyllene in Swiss Mice: Involvement of Benzodiazepine-GABAAergic, Serotonergic and Nitrergic Systems

Current Molecular Pharmacology ◽

10.2174/1874467213666200510004622 ◽

2020 ◽

Vol 14 (1) ◽

pp. 36-51 ◽

Cited By ~ 1

Author(s):

George L. da Silva Oliveira ◽

José C. Correia L. da Silva ◽

Ana P. dos Santos C. L da Silva ◽

Chistiane M. Feitosa ◽

Fernanda R. de Castro Almeida

Keyword(s):

Receptor Antagonist ◽

Molecular Mechanisms ◽

Elevated Plus Maze ◽

Feeding Test ◽

Swiss Mice ◽

Elevated Plus Maze Test ◽

Maze Test ◽

Plus Maze ◽

Gabaergic Receptors ◽

Pre Treatment

Background: Central nervous system disorders such as anxiety, depression and epilepsy are characterized by sharing several molecular mechanisms in common and the involvement of the L-arginine/NO pathway in neurobehavioral studies with β-caryophyllene is still little discussed. Objectives: One of the objectives of the present study was to demonstrate the anxiolytic behavioral effect of β-caryophyllene (β-CBP) in female Swiss mice, as well as to investigate the molecular mechanisms underlying the results obtained. Methods: This study evaluated the neurobehavioral effects of β-CBP using the open field test, rota-rod test, elevated plus maze test, novelty suppressed feeding test, tail suspension test and forced swim test, as well as pilocarpine, pentylenetetrazole and isoniazid-induced epileptic seizure models. Results:: The results demonstrated that the neuropharmacological activities of β-CBP may involve benzodiazepine/GABAergic receptors, since the pre-treatment of β-CBP (200 mg/kg) associated with flumazenil (5 mg/kg, benzodiazepine receptor antagonist) and bicuculline (1 mg/kg, selective GABAA receptor antagonist) reestablished the anxiety parameters in the elevated plus-maze test, as well as the results of reduced latency to consume food in the novelty suppressed feeding test. In addition to benzodiazepine/GABAergic receptors, the neuropharmacological properties of β-CBP may be related to inhibition of nitric oxide synthesis, since pre-treatment with L-arginine (500- 750 mg/kg) reversed significantly the anxiolytic, antidepressant and anticonvulsant activities of β-CBP. Conclusion: The results obtained provide additional support in understanding the neuromolecular mechanisms underlying the anxiolytic, antidepressant and anticonvulsive properties of β-CBP in female Swiss mice.

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