Adrenal Glands
The adrenal glands are small yellow masses that lie on top of each kidney. The outer portion is the cortex (makes up 90% of gland) and the inner portion is the medulla (10% of gland). The major function is to protect from acute and chronic stress by releasing hormones in response to stress or threat of life, the fight-or-flight response. These hormones are epinephrine and norepinephrine (also called catecholamines and considered neurotransmitters) and are secreted by the adrenal medulla, specifically.
Organ response to catecholamines is:
• Increased BP and Pulse (HR)
• Constriction of blood vessels
• Liver releases glucose reserve for immediate energy
• Decreased peristalsis
• Dilation of pupils
• Bronchodilation
The adrenal cortex is responsible for secreting more than 50 steroid hormones such as glucocorticoids & mineral corticoids which are essential to life, and small amounts of androgenic sex hormones (Timby & Smith, 2013, p. 752).
Glucocorticoids (i.e. cortisol):
• Are named for their effects on glucose metabolism
• Major function of cortisol is to increase formation of glucose from glycogen in the liver (gluconeogenesis) causing an increase in blood glucose
• Suppress inflammation
• Help the body understand and respond to stress
Mineralocorticoids
• Are essential for maintenance of fluid and ion balance
• Regulate F&E homeostasis
• Principle one is aldosterone
– functions to promote renal reabsorption of sodium and excretion of potassium and hydrogen ions
–Maintains balance of water, sodium, and potassium; It is the salt & water retaining hormone
Adrenal androgens (sex steroids)
•Are produced and secreted with small amounts of estrogen
•Androgens cause masculinization. Estrogen in men, contributes little to reproductive activity. In women, androgens may function in sexuality and libido.
The adrenal glands are small yellow masses that lie on top of each kidney. The outer portion is the cortex (makes up 90% of gland) and the inner portion is the medulla (10% of gland). The major function is to protect from acute and chronic stress by releasing hormones in response to stress or threat of life, the fight-or-flight response. These hormones are epinephrine and norepinephrine (also called catecholamines and considered neurotransmitters) and are secreted by the adrenal medulla, specifically.
Organ response to catecholamines is:
• Increased BP and Pulse (HR)
• Constriction of blood vessels
• Liver releases glucose reserve for immediate energy
• Decreased peristalsis
• Dilation of pupils
• Bronchodilation
The adrenal cortex is responsible for secreting more than 50 steroid hormones such as glucocorticoids & mineral corticoids which are essential to life, and small amounts of androgenic sex hormones (Timby & Smith, 2013, p. 752).
Glucocorticoids (i.e. cortisol):
• Are named for their effects on glucose metabolism
• Major function of cortisol is to increase formation of glucose from glycogen in the liver (gluconeogenesis) causing an increase in blood glucose
• Suppress inflammation
• Help the body understand and respond to stress
Mineralocorticoids
• Are essential for maintenance of fluid and ion balance
• Regulate F&E homeostasis
• Principle one is aldosterone
– functions to promote renal reabsorption of sodium and excretion of potassium and hydrogen ions
–Maintains balance of water, sodium, and potassium; It is the salt & water retaining hormone
Adrenal androgens (sex steroids)
•Are produced and secreted with small amounts of estrogen
•Androgens cause masculinization. Estrogen in men, contributes little to reproductive activity. In women, androgens may function in sexuality and libido.