Stress-related sleep and memory disorders are important health problem facing many people. The corticotropin-releasing hormone (CRH) neurons in the paraventricular nucleus (PVN) in the hypothalamus play a pivotal role in elevation of cortisol levels in response to stress however neuronal pathway is unknown. In a recent study on laboratory mice, researchers found that stimulation of corticotropin-releasing hormone neurons in the paraventricular nucleus of the hypothalamus (CRHPVN) also produced disrupted sleep and impaired memory, similar to effects produced by the restraint stress, viz., both stress and stimulation of CRHPVN neurons produced same adverse effects on sleep and memory. Conversely, effects on sleep and memory were opposite, i.e., sleep and memory improved when CRHPVN neurons were blocked. The findings suggest that the adverse effects of stress on sleep and memory are regulated by CRHPVN neuronal pathways. Since inhibiting CRHPVN neurons during stress improves sleep and memory functions, targeting CRHPVN neuronal pathways may be a good strategy for treatment of stress-related sleep and memory disorders.
Stress is state of worry and concern caused by difficult situations in life. It is a natural response that prompts us to address the issues and threats before us. Everybody experiences stress at some point in life. It affects our health and wellbeing if not managed and coped properly. One of the key impacts of stress is disruptions in sleep and disorders of memory.
Our body responds to stress by production of cortisol, the “stress hormone.” In stressful situations, hypothalamus secretes corticotropin-releasing hormone (CRH) which in turn stimulate pituitary gland to synthesise corticotropin or adrenocorticotropic hormone (ACTH), as part of the hypothalamic–pituitary–adrenal axis (HPA axis). The corticotropin stimulates adrenal cortex to synthesise and release corticosteroids, mainly glucocorticoids. Elevated cortisol level leads to disrupted sleep pattern and aberrations in circadian rhythm hence occurrence of stress-related sleep disorders. Hypothalamus plays a pivotal role in this, particularly the corticotropin-releasing hormone (CRH) neurons in the paraventricular nucleus (PVN) in the hypothalamus. However, the pathways of how stress causes sleep and memory disorders is unclear. A recent study has looked into this.
To investigate how corticotropin-releasing hormone (CRH) secreting neurons in the paraventricular nucleus (PVN) in the hypothalamus relate with stress-related sleep and memory disorders, the researchers induced stress in the laboratory mice by restraining them in a plastic tube. The stressed mice were found to have disturbed sleep. They also struggled with spatial memory when tested the following day. These effects of stress on sleep and memory in the laboratory mice were on expected lines. The researchers then explored if stimulation of corticotropin-releasing hormone secreting neurons in the paraventricular nucleus (CRHPVN) of the hypothalamus produced the same effects on sleep and memory in unstressed laboratory mice.
Interestingly, activation of corticotropin-releasing hormone neurons in the paraventricular nucleus of the hypothalamus (CRHPVN) also produced disrupted sleep and impaired memory, similar to effects produced by the restraint stress, viz., both stress and stimulation of CRHPVN neurons produced same effects on sleep and memory. Conversely, effects on sleep and memory were opposite, i.e., sleep and memory improved when CRHPVN neurons were blocked.
The above results suggest that the adverse effects of stress on sleep and memory are regulated by CRHPVN neuronal pathways. This is significant. Since inhibiting CRHPVN neurons during stress improves sleep and memory functions, treatment of stress-related sleep and memory disorders by blocking CRHPVN neuronal pathways may become possible in future. The current development is a small step forward in that direction.
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References:
- Wiest, A., et al 2025. Role of hypothalamic CRH neurons in regulating the impact of stress on memory and sleep. Journal of Neuroscience. Published 9 June 2025. DOI: https://doi.org/10.1523/JNEUROSCI.2146-24.2025
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 neurons in the paraventricular nucleus (PVN) in the hypothalamus play a pivotal role in elevation of cortisol levels in response to stress however neuronal pathway is unknown. In a recent study on laboratory mice, researchers found that stimulation of corticotropin-releasing hormone neurons in the paraventricular nucleus of the hypothalamus (CRHPVN) also produced disrupted sleep and impaired memory, similar to effects produced by the restraint stress, viz., both stress and stimulation of CRHPVN neurons produced same adverse effects on sleep and memory. Conversely, effects on sleep and memory were opposite, i.e., sleep and memory improved when CRHPVN neurons were blocked. The findings suggest that the adverse effects of stress on sleep and memory are regulated by CRHPVN neuronal pathways. Since inhibiting CRHPVN neurons during stress improves sleep and memory functions, targeting CRHPVN neuronal pathways may be a good strategy for treatment of stress-related sleep and memory disorders.){kind=link}