endocrine 2a Flashcards
What is an example of a glucocorticoid? What is it’s fxn?
Cortisol.
Running from bears: increase gluconeogenesis and lipolysis, decrease protein synth and glucose uptake.
What is an example of a mineralocorticoid? What is it’s fxn?
Aldosterone.
Out: K+/H+
In: Na+
What disease is an excess in cortisol?
Cushing.
What disease is an excess in aldosterone?
Conn’s.
What disease is insufficient cortisol and aldosterone?
Addison’s.
What zone do the following come from: Aldosterone, Cortisol, Dehydroepiandrosterone, Corticosterone?
Zona Glomerulosa: Aldosterone
Zona Fasciculata: Cortisol and Corticosterone
Zona Reticularis: Dehydroepiandrosterone
How does ACTH stimulate cortisol production in the fasciculata cells?
ACTH > up cAMP > block K+ channels > depolarize > Ca++ enters cell
How does Ang II stimulate aldosterone production in the glomerulosa cells?
Ang II > up PLC > IP3 > open Ca++ channels > increase in cellular Ca++
How does K+ stimulate aldosterone production in the glomerulosa cells?
up K+ > depolarize > Ca++ enters the cell
What are some properties of glucocorticoid receptors in regards to high and low affinity?
a. low affinity
b. respond to cortisol
c. aldosterone concentrations too low to bind
What is the role of 11beta-HSD?
It metabolizes cortisol into cortisone so that it does not bind to high-affinity receptors (MR)
What is the acting and secreting hormone in the zona glomerulosa?
acting: angiotensin, ACTH
secreting: mineralocorticoids
What is the acting and secreting hormone in the zona fasciculata?
acting: corticotropin
secreting: glucocorticoids and androgens
What is the acting and secreting hormone in the zona reticularis?
acting: corticotropin
secreting: glucocorticoids and androgens
What is the acting and secreting hormone in the medulla?
acting: preganglionic fibers
secreting: epi and norepi
Tell me about FLAT PiG.
Basophilic Cells: FSH LH ACTH TSH
Acidophilic:
Prolactin
GH
What do neurophysin I and II do?
I = carrier protein for adh. II = carrier protein for oxytocin.
The hormone and it’s carrier protein are both cleaved from the same prohormone.
Where does alpha-MSH come from?
ACTH
What is the precursor hormone for ACTH?
POMC
LH, FSH, and TSH all have the same what? What is the fxn of each?
All have same alpha subunit.
LH, FSH: stimulate gonads
TSH: stimulate growth and fxn of thyroid.
All are glycoproteins hormones.
What are the somatomammotropin hormones?
GH: growth and development
PRL: lactation, suppress menstration
