Endocrine Part 2 Flashcards
Chief cells produce?
PTH
Principal cells of parathyroid
Chief cells
PTH has what effect on serum electrolyte levels?
Increased [Ca], slightly decreased [PO4]
What makes regulation of the parathyroid unique?
One of very few systems not regulated by pituitary gland → directly regulated by [Ca]
[Ca] serum in the blood is monitored by the parathyroid how?
CaSR protein (Calcium sensing receptor)
How does PTH increase serum [Ca]?
- Osteoclasts
- Ca retention in kidney
- Increased Ca absorption in GI via increasing increased vitamin D
Oxyphils are found in what species?
- Human
- Ox
- horse
Zona glomerulosa aka?
Zona arcuata
Which zone of the cortex is not heavily influenced by ACTH?
Zona glomerulosa
Zona glomerulosa is most influenced by what hormone?
Angiotensin II
Function of zona glomerulosa
Produce mineralocorticoids
Example of mineralocorticoid produces by zona glomerulosa
Aldosteron
Mineralocorticoids produced in the zone glomerulosa have what function?
Increase Na and water retention by kidney
Zona fasciculata produces?
Glucocorticoids (and some androgens)
Example of glucocorticoid produced by zona fasciculata
Cortisol
Zona fasciculata is stimulated to produce glucocorticoids by?
ACTH
Function of glucocorticoids produced by zona fasciculata
- Suppress inflammation
- Increase gluconeogenesis in liver (anabolic)
- Catabolic outside of liver (protein and glycogen breakdown → create substrates for #2)
Result of too much cortisol
Immunosuppression
Zona reticularis produces?
Androgens (and some glucocorticoids)
What hormone stimulated the adrenal cortex (except for the zona glomerulus)?
ACTH
Example of androgen produced by zona reticularis
Androstenedione (testosterone precurosr)
Primary cell in medulla
Chromaffin
Chromaffin cells are also called?
Pheochrome cells
Chromaffin cells in medulla produce?
Catecholamines (epi and norepi)
Medulla is stimulated to produce chromaffin by?
Preganglionic fibers of sympathetic NS
What is Cushing’s syndrome?
Pituitary tumor → overproduction of ACTH → overproduction of glucocorticoids → chronic catabolic state
What is the “third eye”?
Pineal gland
Pineal gland in lower vertebrates acts as?
Light sensing organ
Pineal gland in higher vertebrates
Retains light sensitivity but it buried in the brain
Pineal gland location
Behind pituitary in brain
Main function of pineal gland
Produce melatonin
Functions of melatonin
- Regulate puberty
- Recreational drug metabolism
- Seasonal breeding cycles
- Circardian rythym
Melatonin may regulate puberty through action on the?
Pituitary
5 types of cells in pineal gland
- Pinealocytes
- Interstitial cells
- Perivascular phagocytes
- Penial neurons
- Peptidergic neuron-like cells
Major cells of pineal gland
Pinealocytes
Pinealocyte function
Produce melatonin
Why does pineal gland have perivascular phagocytes?
Not separated by blood-brain barrier → needs immune system
Brain sand aka?
Corpora arenacea
What is “brain sand”?
Calcium deposits in pineal gland