The aim of this study was to investigate the reaction of the hypothalamo-pituitary-adrenocortical (HPA) system to various stressors (fasting, crowding, cold and heat) by measuring blood ACTH and corticosterone (CORT) concentration as well as the cholesterol (CHOL) content in the adrenals. To examine the effects of stress termination, the rats were returned and kept under control conditions for the same period as that of stress duration (supposed recovery period). According to our results HPA system was activated by all the stressors applied. Heat seems to be the strongest stressor since the exposure of animals to a high ambient temperature resulted in the greatest rise of plasma ACTH concentration as well as CORT synthesis and secretion. These values remained elevated after the stress termination i.e. after the rats had been returned to room temperature. Fasting seems to be the weakest stressor given because it causes the smallest increase in blood ACTH and CORT concentrations. Moreover, in refed rats the HPA function was fully recovered. In conclusion, the various stressors applied seem to induce a different response of the HPA system as judged by quantitative changes in ACTH and CORT release.
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Mol Syst Biol
January 2025
Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, 76100, Israel.
Elevated cortisol in chronic stress and mood disorders causes morbidity including metabolic and cardiovascular diseases. There is therefore interest in developing drugs that lower cortisol by targeting its endocrine pathway, the hypothalamic-pituitary-adrenal (HPA) axis. However, several promising HPA-modulating drugs have failed to reduce long-term cortisol in mood disorders, despite effectiveness in other hypercortisolism conditions such as Cushing's syndrome.
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School of Sport, Exercise and Health Sciences, Loughborough University, United Kingdom.
Dysregulation of hypothalamic-pituitary-adrenal axis (HPA axis) and of the autonomic nervous system may link stress throughout the life course with poorer health. This study aims to investigate whether multiple adverse childhood experiences have a long-term impact on markers of these systems - cortisol secretion and heart rate variability - in adulthood. Data were from the Whitehall II cohort study.
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Laboratory of Toxicology, Department of Pharmacological and Biomolecular Science, University of Milan, Via Balzaretti 9, 20133 Milan, Italy.
Endocrine-disrupting chemicals (EDCs) are natural or synthetic substances that are able to interfere with hormonal systems and alter their physiological signaling. EDCs have been recognized as a public health issue due to their widespread use, environmental persistence and the potential levels of long-term exposure with implications in multiple pathological conditions. Their reported adverse effects pose critical concerns about their use, warranting their strict regulation.
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Department of Pharmacology and Therapeutics, Faculty of Basic Medical Sciences, University of Ibadan, Ibadan, Oyo State, Nigeria.
From preclinical and clinical findings, it has been shown that the amygdala is a critical mediator of stress and primary target for stress effects in the brain. We investigated the neuroprotective effect of Ginkgolide B (GB) in repeated restraint stress-induced behavioral deficit and amygdalar inflammation in mice. Mice were orally pre-treated with GB 20 mg/kg 1 h prior to 4 h restraint stress for 21 consecutive days.
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Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Jupiter, FL, USA.
Major Depressive Disorder (MDD) is a common and severe neuropsychiatric condition resulting in irregular alterations in affect, mood, and cognition. Besides the well-studied neurotransmission-related etiologies of MDD, several biological systems and phenomena, such as the hypothalamic-pituitary-adrenal (HPA) axis, reactive oxygen species (ROS) production, and cytokine signaling, have been implicated as being altered and contributing to depressive symptoms. However, the manner in which these factors interact with each other to induce their effects on MDD development has been less clear, but is beginning to be understood.
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