Hypothalamic-Pituitary-Adrenal axis diagramġ. Increased serum cortisol levels inhibit the production of CRH and ACTH via negative feedback, preventing the overproduction of cortisol. The binding of ACTH to the receptors on the adrenal cortex stimulates the release of cortisol into the bloodstream, where it has a wide range of effects.ĥ. ACTH is released into the bloodstream and travels to the adrenal glands, where it binds to specific receptors on the adrenal cortex.Ĥ. This binding causes increased production of adrenocorticotropic hormone (ACTH).ģ. CRH travels in the blood and binds to specific receptors on the pituitary gland. The release of CRH is influenced by stress levels, time of day and serum cortisol levels.Ģ. Corticotropin-releasing hormone (CRH) is secreted by the hypothalamus. Glucocorticoid production is regulated by the hypothalamic-pituitary-adrenal-axis. The release of adrenaline and noradrenaline is under the direct control of the hypothalamus.

The adrenal medulla produces adrenaline and noradrenaline (both of which have similar physiological effects).Īdrenaline and noradrenaline are released during periods of stress, as part of the “ fight or flight” response resulting in increased heart rate, blood pressure and muscle perfusion. It achieves this by promoting the reabsorption of sodium and water, whilst increasing the excretion of potassium. Aiding the metabolism of fat, protein and carbohydratesĪldosterone is also a steroid hormone ( mineralocorticoid) whose main function is to increase blood volume.Increasing blood glucose levels by promoting gluconeogenesis.CortisolĬortisol is a steroid hormone ( glucocorticoid) that is released in response to stress and low blood-glucose levels. The adrenal cortex is responsible for producing cortisol and aldosterone. The glands produce a number of different hormones including cortisol, aldosterone, adrenaline and noradrenaline.Įach gland is composed of an outer cortex and an inner medulla. The adrenal glands are located just above each kidney. You might also be interested in our medical flashcard collection which contains over 1000 flashcards that cover key medical topics.

Adrenal gland hormone