How Brain and Adrenal Clocks Together Control Daily Stress Hormone Levels

Adrenal glucocorticoids (GCs) exhibit a distinct circadian rhythm, peaking at the onset of the active period each day.

• GCs play a crucial role in regulating metabolism, cardiovascular and pulmonary functions, immune responses, and brain activities.
• During stress, GCs are released through activation of the hypothalamic-pituitary-adrenal axis.
• In unstressed states, GCs follow a predictable daily cycle influenced by a central pacemaker and local oscillators.
• The suprachiasmatic nucleus in the hypothalamus coordinates the circadian timing of GCs with local clocks in peripheral tissues.
• Understanding this circadian regulation may have clinical implications for various human diseases.

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