A growing body of data indicates that changes in emotional behavior occur with age. Young Lewis rats are known to display hypofunction of the HPA axis. With age the reactivity of this axis is thought to increase with a concomitant rise in anxiety. In the current study, we investigate how and if the pattern of neuronal activation (measured as c-Fos protein expression) in Lewis rat brains changes with age and in response to novel environments differing in aversiveness. We found that distinct parts of the fear/anxiety circuit (i.e., the amygdalar complex, hippocampus and hypothalamus) undergo diverse age-related changes in response to behavioral challenges. While in the hypothalamus an increase in responsivity to mild stressors was observed with age, no such effect was present in the hippocampus. The amygdalar complex (especially the medial and cortical nuclei) on the other hand exhibited an age-dependent decrease in neuronal activation to mild stressors. This was accompanied by a marked increase in anxiety not correlated with a decline in locomotor activity.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.bbr.2011.07.011 | DOI Listing |
iScience
December 2024
Department of Neurobiology and Collaborative Innovation Center for Brain Science, School of Basic Medicine, The Fourth Military Medical University, Xi'an 710032, China.
The endocannabinoid system (ECS), which is composed of endocannabinoids (eCBs), cannabinoid receptors (CBRs), and associated signaling molecules, has been identified within the brain. In neuropathic pain animal models and patients, long-lasting alterations in the ECS have been observed. These changes of neurons and glial cells in the ECS contribute to the modulation of neuropathic pain.
View Article and Find Full Text PDFNeurosci Biobehav Rev
January 2025
Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Gualtar Campus, Braga 4710-057, Portugal; ICVS/3B's-PT Government Associate Laboratory, Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Guimarães, Portugal. Electronic address:
Fear-induced antinociception (FIA), an instinctive defensive response producing pain suppression in stressful and/or dangerous situations, has been the subject of extensive research to elucidate the mechanisms involved in triggering and controlling pain during emotional disorders. In this systematic review, we synthesized pre-clinical studies that demonstrated the neural hodology and the neurochemical bases of FIA in laboratory animals. The literature search in PubMed, Web of Science, Science Direct, and Scopus, from inception up to July 2022, retrieved 797 articles from which 50 studies were included in this review.
View Article and Find Full Text PDFCurr Top Behav Neurosci
November 2024
Laboratory of Behavioral Genetics, Brain Mind Institute, School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
The functional complexity of brain circuits underlies the broad spectrum of behaviors, cognitive functions, and their associated disorders. Mitochondria, traditionally known for their role in cellular energy metabolism, are increasingly recognized as central to brain function and behavior. This review examines how mitochondria are pivotal in linking cellular energy processes with the functioning of neural circuits that govern fear and anxiety.
View Article and Find Full Text PDFElife
August 2024
Department of Brain and Cognitive Sciences, Scranton College, Ewha Womans University, Seoul, Republic of Korea.
The brain's ability to appraise threats and execute appropriate defensive responses is essential for survival in a dynamic environment. Humans studies have implicated the anterior insular cortex (aIC) in subjective fear regulation and its abnormal activity in fear/anxiety disorders. However, the complex aIC connectivity patterns involved in regulating fear remain under investigated.
View Article and Find Full Text PDFFront Behav Neurosci
July 2024
Department of Pharmacology, University of Minnesota, Minneapolis, MN, United States.
Introduction: Stress and trauma are significant risk factors for many neuropsychiatric disorders and diseases, including anxiety disorders. Stress-induced anxiety symptoms have been attributed to enhanced excitability in circuits controlling fear, anxiety, and aversion. A growing body of evidence has implicated GABAergic neurons of the ventral tegmental area (VTA) in aversion processing and affective behavior.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!