Medial prefrontal cortex oxytocin-opioid receptors interaction in spatial memory processing in rats

2019 ◽  
Vol 209 ◽  
pp. 112599 ◽  
Author(s):  
Reza Salighedar ◽  
Amir Erfanparast ◽  
Esmaeal Tamaddonfard ◽  
Farhad Soltanalinejad
Keyword(s):  
Prefrontal Cortex ◽  
Spatial Memory ◽  
Medial Prefrontal Cortex ◽  
Opioid Receptors ◽  
Memory Processing

scholarly journals Nucleus reuniens is required for encoding and retrieving precise, hippocampal-dependent contextual fear memories in rats

2018 ◽  
Author(s):  
Karthik R. Ramanathan ◽  
Reed L. Ressler ◽  
Jingji Jin ◽  
Stephen Maren
Keyword(s):  
Prefrontal Cortex ◽  
Spatial Memory ◽  
Fear Conditioning ◽  
Medial Prefrontal Cortex ◽  
Thalamic Nucleus ◽  
Nmda Receptor Antagonist ◽  
Pavlovian Fear Conditioning ◽  
Contextual Memory ◽  
Nucleus Reuniens ◽  
Contextual Fear

AbstractThe nucleus reuniens (RE) is a ventral midline thalamic nucleus that interconnects the medial prefrontal cortex (mPFC) and hippocampus (HPC). Considerable data indicate that HPC-mPFC circuits are involved in contextual and spatial memory; however, it is not clear whether the RE mediates the acquisition or retrieval of these memories. To examine this question, we inactivated the RE with muscimol before either the acquisition or retrieval of Pavlovian fear conditioning in rats; freezing served as the index of fear. We found that RE inactivation before conditioning impaired the acquisition of contextual freezing, whereas inactivation of the RE prior to retrieval testing increased the generalization of freezing to a novel context; inactivation of the RE did not affect either the acquisition or expression of auditory fear conditioning. Interestingly, contextual conditioning impairments were absent when retrieval testing was also conducted after RE inactivation. Contextual memories acquired under RE inactivation were hippocampal-independent, insofar as contextual freezing in rats conditioned under RE inactivation was insensitive to intra-hippocampal infusions of the NMDA receptor antagonist, D,L-amino-5-phosophonovaleric acid (APV). Together, these data reveal that the RE supports hippocampal-dependent encoding of precise contextual memories that allow discrimination of dangerous from safe contexts. When the RE is inactive, however, alternate neural systems acquire an impoverished contextual memory that is only expressed when the RE is offline.SIGNIFICANCE STATEMENTThe midline thalamic nucleus reuniens (RE) coordinates communication between the hippocampus and medial prefrontal cortex, brain areas critical for contextual and spatial memory. Here we show that temporary pharmacological inactivation of RE impairs the acquisition and precision of contextual fear memories after Pavlovian fear conditioning in rats. However, inactivating the RE prior to retrieval testing restored contextual memory in rats conditioned after RE inactivation. Critically, we show that imprecise contextual memories acquired under RE inactivation are learned independently of the hippocampus. These data reveal that the RE is required for hippocampal-dependent encoding of precise contextual memories to support the discrimination of safe and dangerous contexts.

scholarly journals Glutamate as a Stressoric Factor for the Ex Vivo Release of Catecholamines from the Rabbit Medial Prefrontal Cortex (mPFC)

Life ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1386
Author(s):  
Bogdan Feliks Kania ◽  
Danuta Wrońska ◽  
Izabela Szpręgiel ◽  
Urszula Bracha
Keyword(s):  
Prefrontal Cortex ◽  
Medial Prefrontal Cortex ◽  
Ex Vivo ◽  
Inhibitory Effect ◽  
Nerve Fibers ◽  
Excitatory Neurotransmitter ◽  
Memory Processing ◽  
Sympathetic Nerve Fibers ◽  
The Central Nervous System ◽  
Emotion Memory

One of the major roles of glutamic acid (Glu) is to serve as an excitatory neurotransmitter within the central nervous system (CNS). This amino acid influences the activity of several brain areas, including the thalamus, brainstem, spinal cord, basal ganglia, and pons. Catecholamines (CAs) are synthesized in the brain and adrenal medulla and by some sympathetic nerve fibers. CAs, including dopamine (DA), norepinephrine (NE), and epinephrine (E), are the principal neurotransmitters that mediate a variety of CNS functions, such as motor control, cognition, emotion, memory processing, pain, stress, and endocrine modulation. This study aims to investigate the effects of the application of various Glu concentrates (5, 50, and 200 µM) on CAs release from rabbit medial prefrontal cortex (mPFC) slices and compare any resulting correlations with CAs released from the hypothalamus during 90 min of incubation. Medial prefrontal cortex samples were dissected from decapitated, twelve-week-old female rabbits. The results demonstrated that Glu differentially influences the direct release of CAs from the mPFC and the indirect release of CAs from the hypothalamus. When under stress, the hypothalamus, a central brain structure of the HPA axis, induces and adapts such processes. Generally, there was an inhibitory effect of Glu on CAs release from mPFC slices. Our findings show that the effect arises from Glu’s action on higher-order motivational structures, which may indicate its contribution to the stress response by modulating the amount of CAs released.

Effects of chronic noise stress on spatial memory of rats in relation to neuronal dendritic alteration and free radical-imbalance in hippocampus and medial prefrontal cortex

2006 ◽  
Vol 399 (1-2) ◽  
pp. 17-22 ◽  
Author(s):  
Sundaramahalingam Manikandan ◽  
Moorthy K Padma ◽  
Ramasundaram Srikumar ◽  
Narayanaperumal Jeya Parthasarathy ◽  
Arumugam Muthuvel ◽  
...  
Keyword(s):  
Prefrontal Cortex ◽  
Free Radical ◽  
Spatial Memory ◽  
Medial Prefrontal Cortex ◽  
Noise Stress

Ventral Hippocampal Neurons Project Axons Simultaneously to the Medial Prefrontal Cortex and Amygdala in the Rat

2006 ◽  
Vol 96 (4) ◽  
pp. 2134-2138 ◽  
Author(s):  
Akinori Ishikawa ◽  
Shoji Nakamura
Keyword(s):  
Prefrontal Cortex ◽  
Spatial Memory ◽  
Medial Prefrontal Cortex ◽  
Hippocampal Neurons ◽  
Ventral Hippocampus ◽  
Fluorescent Tracers ◽  
Afferent Projections ◽  
Electrophysiological Evidence ◽  
Antidromic Responses ◽  
The Individual

The ventral hippocampus (VH) may have an important role in spatial memory processes and emotional behaviors through connections with the medial prefrontal cortex (mPFC) and amygdala. Although the mPFC and amygdala receive afferent projections from the VH, it has not been determined whether the individual VH neurons project to both the mPFC and the amygdala. In this study, antidromic responses to the mPFC and amygdala stimulation were evoked in single VH neurons. In addition, VH neurons were retrogradely double-labeled with fluorescent tracers injected in the mPFC and amygdala. VH neurons projecting to both the mPFC and amygdala were predominantly located in the subiculum and CA1 and bifurcated near or at the soma. Our anatomical and electrophysiological evidence for the presence of VH neurons projecting to both the mPFC and amygdala provides a previously unrecognized pathway from the hippocampus that simultaneously activates the mPFC and amygdala.

scholarly journals Transient Inactivation of the Medial Prefrontal Cortex and Ventral Hippocampus Impairs Active Place Avoidance Retrieval on a Rotating Arena

2021 ◽  
Vol 15 ◽  
Author(s):  
Daniela Cernotova ◽  
Ales Stuchlik ◽  
Jan Svoboda
Keyword(s):  
Prefrontal Cortex ◽  
Spatial Memory ◽  
Medial Prefrontal Cortex ◽  
Ventral Hippocampus ◽  
Avoidance Task ◽  
Exact Role ◽  
Spatial Coordination ◽  
Place Avoidance ◽  
Long Evans

It is well known that communication between the medial prefrontal cortex (mPFC) and the ventral hippocampus (vHPC) is critical for various cognitive and behavioral functions. However, the exact role of these structures in spatial coordination remains to be clarified. Here we sought to determine the involvement of the mPFC and the vHPC in the spatial retrieval of a previously learned active place avoidance task in adult male Long-Evans rats, using a combination of unilateral and bilateral local muscimol inactivations. Moreover, we tested the role of the vHPC-mPFC pathway by performing combined ipsilateral and contralateral inactivations. Our results showed not only bilateral inactivations of either structure, but also the combined inactivations impaired the retrieval of spatial memory, whereas unilateral one-structure inactivations did not yield any effect. Remarkably, muscimol injections in combined groups exerted similar deficits, regardless of whether the inactivations were contralateral or ipsilateral. These findings confirm the importance of these structures in spatial cognition and emphasize the importance of the intact functioning of the vHPC-mPFC pathway.

Sign in / Sign up

Export Citation Format

Share Document