II. Pathophysiology
- Aldosterone
-
Cortisol
- Addison's Disease (Adrenal Insufficiency)
- Cushings Disease
- Androgens
- Congenital Adrenal Hyperplasia
- 21-Hydroxylase deficiency is most common
- Congenital Adrenal Hyperplasia
- Epinephrine and Norepinephrine (Adrenal Medulla)
III. Physiology: General
- Images
-
Cholesterol is precursor for 5 steroid Hormone classes
- Progestagens (e.g. Progesterone)
- Glucocorticoids (e.g. Cortisol)
- Mineralcorticoids (e.g. Aldosterone)
- Androgens (e.g. Testosterone)
- Estrogens
- Synthesis sites
- Adrenal Cortex: Glucocorticoids, Mineralcorticoids
- Women
- Men
IV. Physiology: Step 1 (Steroid Synthesis - Cholesterol to Precursors)
-
Cholesterol converted to Pregnenolone
- Stimulated by ACTH release from anterior pituitary
- Key enzyme: Desmolase
- Pregnenolone converted to Progesterone
- Pregnenolone is precursor of all steroids
- Key enzyme: 3-B-Hydroxysteroid Dehydrogenase
-
Progesterone converted to 17-a-hydroxyprogesterone
- Key enzyme: 17-Hydroxylase
- 17-a-hydroxyprogesterone is precursor
- Cortisol Synthesis (Go to step 2)
- Aldosterone Synthesis (Go to Step 4)
- 17-a-hydroxyprogesterone converted to Androstenedione
- Key enzyme: 3-B-Hydroxysteroid Dehydrogenase
- Androstenedione is sex Hormone precursor (see Step 3)
- Estrone
- Testosterone
- Estradiol
V. Physiology: Step 2 (Cortisol Synthesis from 17-a-hydroxyprogesterone)
VI. Physiology: Step 3 (Sex Hormones from Androstenedione)
- Androstenedione converted to Estrone or
-
Androstenedione converted to Testosterone
- Testosterone converted to Estradiol
VII. Physiology: Step 4 (Aldosterone from Progesterone)
-
Progesterone converted to 11-Deoxycorticosterone
- Key enzyme: 21-Hydroxylase
- 11-Deoxycorticosterone converted to Cortisosterone
- Key enzyme: 11-Hydroxylase
- Corticosterone converted to Aldosterone
- Aldosterone