PBIO LECT 19

zona glomerulosa secretes

aldosterone (salt)

zona fasciculata secretes

glucocorticoids (sugar)

zona reticularis secretes

sex hormones

adrenal medulla secretes

catecholamines

regulatory of salt balance and extracellular volume

zona glomerulosa

Raise plasma glucose, immunosuppressive, anti-inflammatory

zona fasciculata

Weak androgens, implicated in aggression, sexual attraction, adrenarche. Source of about 1/2 the androgens found in women

zona reticularis

Raise plasma glucose, increase heart rate, flight or fight response

adrenal medulla

aldosterone __ blood pressure via RAAS (caused by high [K+] & too much pressure @ heart)

increases

congenital adrenal hyperplasia (CAH) is __ & will cause salt loss/dehydration, virilizing in females & insulin resistance

halt in aldosterone synthesis

problem with those enzymes with cause CAH (“salt wasting”):

21-hydroxylase (common), 11-B-hydroxylase, aldosterone synthase (rare)

development of male-like characteristics due to excess androgens

virilizing

control of hormone secretion is at

hypothalamic-pituitary axis

• is a steroid hormone

• A biomarker for stress

• Biologic Half-life 90 min.

• Inhibits peripheral use of glucose

• By inhibiting GLUT4 translocation

• Promotes gluconeogenesis

• Promotes lipolysis

• Counteracts Insulin

• Promotes skeletal muscle breakdown

• Reduces bone formation

• Promotes fetal lung maturation

• Blocks cytokine production by immune cells

• Suppresses the immune system

• the most important and abundant glucocorticoid, is essential for proper water, carbohydrate, protein, and fat metabolism

cortisol

(issue with cortisol)

• Also called primary adrenal insufficiency

• Results from autoimmune damage to the adrenal glands

• low cortisol & high ACTH

• diagnosed by ACTH stimulation (inject ACTH & monitor cortisol response)

Addison’s disease

(issue with cortisol)

• Often caused by a pituitary tumor

• Treated by removal of the tumor

• high cortisol & high ACTH

• diagnosed by 24hr urine or late night salivary test of cortisol levels

pituitary Cushing’s disease

__ inhibits feeding & increases melanin production in melanocytes in Addison’s disease

a-MSH

(issue with cortisol)

• low cortisol, low ACTH

• Features: Low energy, NO darkened skin, electrolytes OK

• Causes: Pituitary damage, Long-term cortisol use withdrawal

• Treatment: Cortisol supplementation

secondary adrenal insufficiency

(issue with cortisol)

• High Cortisol, Low ACTH

• Often caused by an adrenal tumor

• Treatment: Surgery, radiation, steroidogenesis inhibitor

Adrenal Cushing’s syndrome

(issue with cortisol)

• High Cortisol, Low ACTH

• Excess cortisol intake

• Treatment: Stop taking cortisol/treatment

exogenous Cushing’s disease

precursor for most hormones

cholesterol