Hyperactivity of the hypothalamo-pituitary-adrenocortical (HPA) axis is linked with age-related decrements in cognition and neuronal survival. However, the nature and extent of age-related HPA axis deficits vary considerably across and indeed, within strains. The current study was designed to assess variance in HPA axis function using two rodent models commonly used in aging studies: Fischer 344 (F344) and F344/Brown-Norway F1 hybrid rats (F344/BN). We examined both basal and stress-induced ACTH and corticosterone (CORT) release in two stress contexts thought to differ in intensity: novel environment ('mild') and restraint ('intense'). Variability of the data was tested with a modification of the Brown-Forsythe test of homoscedasticity. The results indicated that F344 rats exhibit greater peak HPA responses. Furthermore, in most cases variability was increased in aged rats relative to young and middle-aged rats of the same strain, indicative of the emergence of individual differences in stress responsivity amongst older rats. The results suggest that these older rat strains may be useful models to further assess individual differences in neuroendocrine aging.
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http://dx.doi.org/10.1016/j.physbeh.2008.07.024 | DOI Listing |
Psychoneuroendocrinology
January 2025
Department of Psychiatry, University of Michigan - Michigan Medicine, USA.
Prenatal stress has a well-established link to negative biobehavioral outcomes in young children, particularly for girls, but the specific timing during gestation of these associations remains unknown. In the current study, we examined differential effects of timing of prenatal stress on two infant biobehavioral outcomes [i.e.
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January 2025
Research Center of Psychiatry and Behavioral Sciences, Tabriz University of Medical Sciences, Tabriz, Iran; Aging Research Institute, Tabriz University of Medical Sciences, Tabriz, Iran. Electronic address:
While benzodiazepines have been a mainstay of the pharmacotherapy of anxiety disorders, their short-term efficacy and risk of abuse have driven the exploration of alternative treatment approaches. The endocannabinoid (eCB) system has emerged as a key modulator of anxiety-related processes, with evidence suggesting dynamic interactions between the eCB system and the GABAergic system, the primary target of benzodiazepines. According to the existing literature, the activation of the cannabinoid receptors has been shown to exert anxiolytic effects, while their blockade or genetic deletion results in heightened anxiety-like responses.
View Article and Find Full Text PDFStress
December 2025
Division of General Internal Medicine, Mayo Clinic, Jacksonville, Florida, USA.
In the current age of technological advancement, stress has emerged as a silent pandemic affecting individuals, especially young generations, globally. Factors such as increased competition, social pressures fueled by social media and smartphones, and a sense of diminished control in the face of modern challenges contribute to rising stress levels. In addition to the negative implications on mental well-being, stress affects physiological processes such as the menstrual cycle.
View Article and Find Full Text PDFNutrients
January 2025
School of Pharmacy, Shaoyang University, Shaoyang 422000, China.
Depression, a serious mental illness, is characterized by high risk, high incidence, persistence, and tendency to relapse, posing a significant burden on global health. The connection between depression and gut microbiota is an emerging field of study in psychiatry and neuroscience. Understanding the gut-brain axis is pivotal for understanding the pathogenesis and treatment of depression.
View Article and Find Full Text PDFBiology (Basel)
January 2025
Federal Medical Biophysical Center of Federal Medical Biological Agency, 123098 Moscow, Russia.
Understanding the regulatory mechanisms of stress-induced immunosuppression and developing reliable diagnostic methods are important tasks in clinical medicine. This will allow for the development of effective strategies for the prevention and treatment of conditions associated with immune system dysfunction induced by chronic stress. The purpose of this review is to conduct a comprehensive analysis and synthesis of existing data on the regulatory mechanisms of stress-induced immunosuppression.
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