Neostriatum neuronal TRPV 1 -signalling mediates striatal anandamide at high concentration facilitatory influence on neostriato-nigral dishinhibitory GABAergic connections.

Autor: da Silva JA; Ribeirão Preto Medical School of the University of São Paulo (FMRP-USP), Department of Pharmacology, Laboratory of Neuroanatomy and Neuropsychobiology, Ribeirão Preto, São Paulo, Brazil; Behavioural Neuroscience Institute (INeC), Ribeirão Preto, São Paulo, Brazil. Electronic address: ju.silva@usp.br., Almada RC; Ribeirão Preto Medical School of the University of São Paulo (FMRP-USP), Department of Pharmacology, Laboratory of Neuroanatomy and Neuropsychobiology, Ribeirão Preto, São Paulo, Brazil; São Paulo State University (UNESP), School of Science and Literature, Department of Biological Sciences, Assis, São Paulo, Brazil; Behavioural Neuroscience Institute (INeC), Ribeirão Preto, São Paulo, Brazil., Falconi-Sobrinho LL; Ribeirão Preto Medical School of the University of São Paulo (FMRP-USP), Department of Pharmacology, Laboratory of Neuroanatomy and Neuropsychobiology, Ribeirão Preto, São Paulo, Brazil; Behavioural Neuroscience Institute (INeC), Ribeirão Preto, São Paulo, Brazil., Pigatto GR; Ribeirão Preto Medical School of the University of São Paulo (FMRP-USP), Department of Pharmacology, Laboratory of Neuroanatomy and Neuropsychobiology, Ribeirão Preto, São Paulo, Brazil; Behavioural Neuroscience Institute (INeC), Ribeirão Preto, São Paulo, Brazil., Hernandes PM; Ribeirão Preto Medical School of the University of São Paulo (FMRP-USP), Department of Pharmacology, Laboratory of Neuroanatomy and Neuropsychobiology, Ribeirão Preto, São Paulo, Brazil; São Paulo State University (UNESP), School of Science and Literature, Department of Biological Sciences, Assis, São Paulo, Brazil., Coimbra NC; Ribeirão Preto Medical School of the University of São Paulo (FMRP-USP), Department of Pharmacology, Laboratory of Neuroanatomy and Neuropsychobiology, Ribeirão Preto, São Paulo, Brazil; Behavioural Neuroscience Institute (INeC), Ribeirão Preto, São Paulo, Brazil; NAP-USP-Neurobiology of Emotions Research Centre (NuPNE), Ribeirão Preto Medical School of the University of São Paulo, Ribeirão Preto, São Paulo, Brazil. Electronic address: nccoimbr@fmrp.usp.br.
Jazyk: angličtina
Zdroj: Brain research bulletin [Brain Res Bull] 2023 Jan; Vol. 192, pp. 128-141. Date of Electronic Publication: 2022 Nov 19.
DOI: 10.1016/j.brainresbull.2022.11.014
Abstrakt: Rationale: Several lines of evidence have demonstrated that the cannabinoid type 1 receptor (CB 1 ) is found in the caudate nucleus and putamen (CPu) in addition to the substantia nigra pars reticulata (SNpr). Here, we investigated the role of endocannabinoid neuromodulation of striato-nigral disinhibitory projections on the activity of nigro-collicular GABAergic pathways that control the expression of unconditioned fear-related behavioural responses elicited by microinjections of the GABA A receptor selective antagonist bicuculline (BIC) in the deep layers of the superior colliculus (dlSC).
Methods: Fluorescent neural tract tracers were deposited in either CPu or in SNpr. Wistar rats received injection of vehicle, anandamide (AEA), either at low (50 pmol) or high (100 pmol) concentrations in CPu followed by bicuculline microinjections in dlSC.
Results: Connections between CPu, the SNpr and dlSC were demonstrated. The GABA A receptor blockade in dlSC elicited panic-like behaviour. AEA at the lowest concentration caused a panicolytic-like effect that was antagonised by the CPu pretreatment with AM251 at 100 pmol. AEA at the highest concentration caused a panicogenic-like effect that was antagonised by the CPu pretreatment with 6-iodonordihydrocapsaicin (6-I-CPS) at different concentrations (0.6, 6, 60 nmol).
Conclusion: These findings suggest that while pre-synaptic CB1-signalling subserves an indirect facilitatory effect of AEA on striato-nigral pathways causing panicolytic-like responses through midbrain tectum enhanced activity, post-synaptic TRPV 1 -signalling in CPu mediates AEA direct activation of striato-nigral disinhibitory pathways resulting in increasing dlSC neurons activity and a panicogenic-like response. All these actions seem to depend on the interface with the nigro-collicular inhibitory GABAergic pathways.
Competing Interests: Declaration of Competing Interest The authors declare that there are no conflicts of interest concerning the presented work.
(Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)
Databáze: MEDLINE
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