Adrenal Glands Flashcards
What are the 2 components of the adrenal gland?
- Adrenal cortex.
- Adrenal medulla.
List the classes of steroid hormones synthesised and released from the adrenal cortex.
1 - Glucocorticoids.
2 - Mineralocorticoids.
3 - Adrenal androgens.
What class of hormones are synthesised and released from the adrenal medulla?
Catecholamines.
List the layers of the adrenal cortex from superficial to deep.
1 - Zona glomerulosa.
2 - Zona fasciculata.
3 - Zona reticularis.
What class of hormones are synthesised at the zona glomerulosa?
Mineralocorticoids.
What class of hormones are synthesised at the zona fasciculata?
Glucocorticoids.
What class of hormones are synthesised at the zona reticularis?
Androgens.
List 2 mineralocorticoids.
1 - Aldosterone.
2 - DOC.
Give an example of a glucocorticoid.
Cortisol.
List 2 adrenal androgens.
1 - DHEA.
2 - Androstenedione.
What is the precursor molecule steroidogenesis?
Cholesterol.
What is the name of the disease that causes an excess of glucocorticoids?
Cushing’s syndrome.
What is the name of the disease that causes an excess of mineralocorticoids?
Conn’s syndrome.
What is the name of the disease that causes an excess of adrenal androgens?
Hyperandrogenism.
What is the name of the disease that causes an excess of catecholamines?
Phaeochromocytoma (a tumour).
List 2 causes of excess adrenal activity.
1 - Adrenal tumours.
2 - Congenital adrenal hyperplasia.
Are steroid hormones lipophilic or hydrophilic?
Lipophilic.
What are permissive actions of drugs?
Actions that do not directly initiate but allow other actions to occur in the presence of other factors.
List 3 actions of glucocorticoids.
1 - Increase glucose mobilisation.
2 - Maintenance of circulation.
3 - Immunomodulation.
List 3 ways by which glucocorticoids increase glucose mobilisation.
1 - By augmenting gluconeogenesis.
2 - Via amino acid generation.
3 - By increasing lipolysis.
List 2 ways by which glucocorticoids maintain circulation.
1 - By maintaining vascular tone.
2 - By controlling the salt and water balance.
What is the role of glucocorticoids in immunomodulation?
Glucocorticoids dampen the immune response.
List the proteins that bind to glucocorticoids in the blood, and give the relative abundance of each.
- 90% of glucocorticoids are bound to corticosteroid-binding globulin (CBG).
- 5% bound to albumin.
- 5% free and bioavailable.
What is the effect of inflammation on corticosteroid-binding globulin (CBG)?
CBG decreases with inflammation.
Define diurnal.
Occurring during daylight hours.
Define circadian.
Occurring once every 24 hours.