Stress is the physiological response to hostile situations, that can result in maladaptive mechanisms and became a potential risk factor for many neuropsychiatric disorders, even after a single exposure to stressor. The mPFC plays a central role in the regulation of the stress response. Stress modifies the Glu transmission in this area, e.g. in acute foot-shock (FS) stress models, an increase in depolarizationevoked Glu release from synaptosomes was shown 1 day and 1 hour after stress exposure. 1 day after, there is also an increase in the number of synapses and a decreased development of the dendritic arbour of principal, similarly to what happens in chronically stressed animals. The work described in this thesis aims to investigate the time course of the effects of acute stress, FS protocol, on excitatory synaptic transmission of neurons in cortical layers 2/3 (L2-3) and 5 (L5) in the prelimbic area of the mPFC of adult rats. Likewise, investigating the possible use of ketamine at low doses for the rescue of FS effects on synaptic transmission, as suggested by the involvement of mPFC in the antidepressant action of this treatment. Using the whole-cell patch-clamp technique, we recorded spontaneous and miniature excitatory transmission, in both L2-3 an L5. The same technique was used to record spontaneous excitatory and inhibitory current in L2-3 to estimate the E/I ratio. Our data confirm an early FS stress-induced enhancement of Glu transmission in L2-3, linked to the activation of a few strong synapses, and not paralleled by an increase in the E/I ratio in single neurons. On the contrary, 1 day after FS, the excitatory Glu conductance is increased in parallel with an increase in the E/I balance. Ketamine at this time increases the frequency of sEPSCs.

Stress acuto, ketamina e trasmissione sinaptica nella mPFC di ratto adulto / Scarzella Salerno - : . , 2021. ((33. ciclo, Anno Accademico 2019/2020.

Stress acuto, ketamina e trasmissione sinaptica nella mPFC di ratto adulto

SALERNO SCARZELLA
2021

Abstract

Stress is the physiological response to hostile situations, that can result in maladaptive mechanisms and became a potential risk factor for many neuropsychiatric disorders, even after a single exposure to stressor. The mPFC plays a central role in the regulation of the stress response. Stress modifies the Glu transmission in this area, e.g. in acute foot-shock (FS) stress models, an increase in depolarizationevoked Glu release from synaptosomes was shown 1 day and 1 hour after stress exposure. 1 day after, there is also an increase in the number of synapses and a decreased development of the dendritic arbour of principal, similarly to what happens in chronically stressed animals. The work described in this thesis aims to investigate the time course of the effects of acute stress, FS protocol, on excitatory synaptic transmission of neurons in cortical layers 2/3 (L2-3) and 5 (L5) in the prelimbic area of the mPFC of adult rats. Likewise, investigating the possible use of ketamine at low doses for the rescue of FS effects on synaptic transmission, as suggested by the involvement of mPFC in the antidepressant action of this treatment. Using the whole-cell patch-clamp technique, we recorded spontaneous and miniature excitatory transmission, in both L2-3 an L5. The same technique was used to record spontaneous excitatory and inhibitory current in L2-3 to estimate the E/I ratio. Our data confirm an early FS stress-induced enhancement of Glu transmission in L2-3, linked to the activation of a few strong synapses, and not paralleled by an increase in the E/I ratio in single neurons. On the contrary, 1 day after FS, the excitatory Glu conductance is increased in parallel with an increase in the E/I balance. Ketamine at this time increases the frequency of sEPSCs.
“stress” , “electrophysiology” , “acute stress”, “mPFC”, “mEPSCs”, “sEPSCs”, “E/I ratio”, “synaptic transmission”, “ketamine”, “adult rats”
Stress acuto, ketamina e trasmissione sinaptica nella mPFC di ratto adulto / Scarzella Salerno - : . , 2021. ((33. ciclo, Anno Accademico 2019/2020.
File in questo prodotto:
File Dimensione Formato  
Floramarida Salerno Scarzella_PhD Thesis.pdf

embargo fino al 15/03/2023

Tipologia: Tesi di dottorato
Licenza: DRM non definito
Dimensione 3.21 MB
Formato Adobe PDF
3.21 MB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/11383/2115189
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact