Effects of AP5 infusion into the lateral ventricle on the activities and hippocampal electrical patterns of sleep episodes in rats.

Physiol Behav

Cukurova University, Medical Faculty, Division of Neurophysiology, Department of Physiology, 01330 Balcali, Adana/Turkey.

Published: February 2006

AI Article Synopsis

  • NMDA receptors in the hippocampus, typically linked to learning and memory, have an under-explored role in sleep-related processes.
  • Infusing NMDA receptor antagonist AP5 in rats showed that while it initially didn't alter sleep stages, it delayed the onset of paradoxical sleep and increased SPW amplitude during slow-wave sleep.
  • Repeated infusions of AP5 enhanced slow-wave sleep but hampered paradoxical sleep and awake states, highlighting the importance of NMDA receptors for regulating sleep activities related to SPWs and theta rhythm generation.

Article Abstract

Although N-methyl-D-aspartate (NMDA) receptors of the hippocampus are mainly associated with learning and memory that might occur "on-line" during sharp waves (SPWs) and theta-rhythm, the participation of hippocampal NMDA receptors in sleep-related processes has not been well studied. In this study, the activity of sleep episodes, hippocampal SPWs and theta-rhythm were recorded in rats received a repeated infusion of NMDA receptor antagonist, D,L-2-amino-5-phosphonopentanoic acid (AP5), into the lateral ventricle in a 5-h daytime sleep. The first trial AP5 infusion (30 mM/2 microl) did not change measures of the activity of slow wave sleep (SWS), paradoxical sleep (PS) and awake episodes, but induced a delay in the latency of the first onset of PS; in the hippocampal EEG, it increased the amplitude of SPWs within SWS and shifted the amplitude/spectral power of theta-rhythm from high to low frequency within PS. The repeated AP5 infusion augmented the activity of SWS, and impaired PS and awake episodes; in the EEG-sleep picture, it maintained high scores of SPWs with the complete blockade of theta-rhythm generation. When AP5 rat was woken, the theta-rhythm was seen during exploratory behavior. These findings provide evidence that hippocampal NMDA receptors via SPWs or directly associated with the synaptic events of theta-rhythm generation are critical for the PS activities.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.physbeh.2005.11.008DOI Listing

Publication Analysis

Top Keywords

ap5 infusion
12
nmda receptors
12
lateral ventricle
8
sleep episodes
8
spws theta-rhythm
8
hippocampal nmda
8
awake episodes
8
theta-rhythm generation
8
theta-rhythm
6
hippocampal
5

Similar Publications

Vasopressin regulates social play behavior in sex-specific ways through glutamate modulation in the lateral septum.

Neuropsychopharmacology

September 2024

Neurobiology of Social Behavior Laboratory, Department of Psychology and Neuroscience Program, Michigan State University, East Lansing, MI, USA.

Understanding the neural basis of social play in juvenile rats may ultimately help restore social play deficits in autistic children. We previously found that administration of a vasopressin (AVP) V1a receptor (V1aR) antagonist into the lateral septum (LS) increased social play behavior in male juvenile rats and decreased it in females. Here, we demonstrate that glutamate, but not GABA, is involved in this sex-specific regulation.

View Article and Find Full Text PDF

The anterior retrosplenial cortex (aRSC) integrates multimodal sensory information into cohesive associative recognition memories. Little is known about how information is integrated during different learning phases (i.e.

View Article and Find Full Text PDF

It is widely accepted that Pavlovian fear conditioning requires activation of NMDA receptors (NMDARs) in the basolateral amygdala complex (BLA). However, it was recently shown that activation of NMDAR in the BLA is only required for fear conditioning when danger occurs unexpectedly; it is not required for fear conditioning when danger occurs as expected. This study tested the hypothesis that NMDARs in the BLA are engaged for Pavlovian fear conditioning when an animal's predictions regarding danger are in error.

View Article and Find Full Text PDF

Optogenetic stimulation of Kiss1 terminals in the AVPV induces surge-like luteinizing hormone secretion glutamate release in mice.

Front Endocrinol (Lausanne)

November 2022

Department of Women and Children's Health, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom.

Kisspeptin neurons are mainly located in the arcuate (Kiss1, vis-à-vis the GnRH pulse generator) and anteroventral periventricular nucleus (Kiss1, vis-à-vis the GnRH surge generator). Kiss1 send fibre projections that connect with Kiss1 somata. However, studies focused on the role of Kiss1 neurons in the LH surge are limited, and the role of Kiss1 projections to AVPV (Kiss1) in the preovulatory LH surge is still unknown.

View Article and Find Full Text PDF

It is widely accepted that activation of NMDA receptors (NMDAR) is necessary for the formation of fear memories in the basolateral amygdala complex (BLA). This acceptance is based on findings that blockade of NMDAR in the BLA disrupts Pavlovian fear conditioning in rodents when initially innocuous stimuli are paired with aversive and unexpected events (surprising foot shock). The present study challenges this acceptance by showing that the involvement of NMDAR in Pavlovian fear conditioning is determined by prediction errors in relation to aversive events.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!