Endocrinology Flashcards
(26 cards)
What are the resulting hormone levels from GHRH deficiency
Low GH/IGF-1
What are the resulting hormone levels with GH deficiency?
If it is a problem with GH gene expression and release, there are low levels of GH and IGF-1
If it is a problem with the GH receptor on the liver, there will be high levels of GH and no negative feedback and low levels of IGF-1
What are the hormonal results of Laron dwarfism?
GH and IGF-1 levels are normal
What is the structure of prolactin?
A single chain polypeptide with 4 alpha helices
What does prolactin do in amphibians?
Prevents metamorphosis
What does prolactin do in fish?
Osmoregulation
What type of gland is the mammary gland?
An exocrine gland
What is the structure of mammary gland?
An alveolar cell surrounded by myoepithelial cells.
How does actual milk production work?
Prolactin tells the alveolar to make milk products and oxytocin tells the alveolar cells to release milk
What are glycoproteins?
Polypeptides that have carbohydrate groups covalently linked
What is glycoproteins structure?
Heterodimers with an alpha and beta subunit
What part of the glycoproteins is different between hormone?
The beta subunit
What 4 hormones are glycoproteins?
FSH, TSH, LH, and HCG
What are the steps for biosynthesis of glycoproteins?
1) the alpha and B subunit gene is expressed
2) the mRNAs are translated at the ER
3) signal peptidase cuts off signal sequence
4) glycosylation occurs in rER
5) the heterodimer is assembled in the ER by H bonding and moves to the golgi to be packaged into secretory vesicles
What is the mode of action of glycoprotein hormone?
The beta subunit finds the target cell and the alpha subunit bonds to the GPCR to activate the G protein and the ardenylyl cyclase, then the biological response occurs through a cAMP/PKA system and the PKA mediates the biological response
What are the four embryonic cell types?
Gamete precursor cells, pre-sertoli cells, pre-leydig cells, pre-follicular cells
Which three embryonic cell types are important to males?
Gamete precursor cells, pre-sertoli cells, and pre-leydig cells
What is the order of differentiation of embryonic cell types in males?
Pre-sertoli to sertoli, pre-leydig to leydig, gamete precursor—> gamete
What 2 cell types are important to the embryonic development of genetic females?
Pre-follicular cells and pre-gamete cells
What hormone does the Sertoli cell release? Which hormone does the leydig cell release?
AMH-sertoli; testosterone-leydig
If AMH is present what happens internally?
The Müllerian duct is degraded and T diffentiates the wolffian duct into the bad deferens
If there is no AMH what happens internally?
The Müllerian duct turns into the Fallopian tube and the wolffian duct undergoes programmed cell death
Which sex develops with the absence of chemical signals?
Female
What does the genital condition look like at 4 1/2 weeks?
The urethral slit, Müllerian and wolffian ducts are present, and phallus and genital swelling
