Term
| When are positive feedback mechanisms used? |
|
Definition
-blood clotting
-ovulation
-parturition |
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|
Term
| What is an endocrine gland |
|
Definition
| tissue which releases a substance into the blood stream, which will travel to create a change in a target cell |
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|
Term
| What are the classes of hormones? |
|
Definition
FAPPS
Fatty acid derivatives (prostaglandins)
AA derivatives (epinephrine)
Peptides (hypothalamic factors)
Proteins (growth hormone)
steroids (cholesterol der. e.e. glucocorticoids) |
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|
Term
| What is an intracrine cell? |
|
Definition
| cell that produces a hormone which stays within the cell and targets an organelle within it |
|
|
Term
| What is an autocrine cell? |
|
Definition
| cell that produces a hormone which exits the cell and then targets it from the outside |
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|
Term
| What is a juxtacrine cell? |
|
Definition
| cell that produces a hormone which creates a change in the mmb of the cell, which subsequently changes the mmb of the adjacent cell (hormone never leaves its' original cell) |
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Term
| What is different about the synthesis & release of steroid hormones? |
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Definition
they are synth in SER & mitochondria, and then diffuse out of the cell after synthesis (they are never stored)
=constitutive secretion |
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|
Term
| preprohormones are stored in the.... |
|
Definition
|
|
Term
|
Definition
| hormone that needs to be cleaved once to become active |
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|
Term
| Prohormone is cleaved in the... |
|
Definition
|
|
Term
| Where are the receptors for steroid & thyroid hormones found? |
|
Definition
thyroid - targets are in the nucleus
steroid - receptors are in the cytoplasm |
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Term
| How do ion channel receptors work? |
|
Definition
| hormone binds to receptor on the outside of the cell, which opens ion channels to allow them to move in/out |
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|
Term
| What hormones use ion channel receptors? |
|
Definition
| growth factors, Ach receptors in the synaptic cleft |
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|
Term
| How do tyrosine kinase receptors work? |
|
Definition
1. Hormone binds to LBD outside of cell
2. Receptor dimerizes (pair binds) to activate tyrosine kinase.
3. TK can create a protein phosphorylation cascade |
|
|
Term
| What type of receptor does insulin use? |
|
Definition
|
|
Term
| What type of receptor does growth hormone use? |
|
Definition
|
|
Term
| How do cytokine receptors work? |
|
Definition
1. Hormone binds outside cell, the 2 domains of the receptor couple.
2. JAK is recruited to the intracellular domain of the receptor, is activated once it binds.
3. JAK catalyzes phoshporylation of STAT
4. STAT-P activates signal transducers & transcription factors to change gene expression. |
|
|
Term
| How do cAMP G-protein receptors work? |
|
Definition
1. Hormone binds to extracellular domain of receptor
2. G protein releases alpha subunit (can be s or i)
3. Alpha activates adenylate cyclase
4. AC catalyzes conversion of ATP to cAMP
5. cAMP activates carious hormones, or transcription factors |
|
|
Term
| How do phospholipase C G-protein receptors work? |
|
Definition
1. Hormone binds to extracellular domain of receptor
2. G protein releases alpha-Q subunit
3. Alpha-Q activates phospholipase C.
4. PlpC can make DAG (activates protein kinase C) or IP3 (releases Ca2+ from ER) |
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|
Term
| The posterior lobe of the pituitary (neurohypophysis) originates from the... |
|
Definition
| neuroectoderm (outgrowth of the hypothalamus) |
|
|
Term
| The anterior lobe of the pituitary (adenophypohysis) develops from the... |
|
Definition
|
|
Term
| The pars nervosa comprises the (posterior/anterior) pituitary |
|
Definition
|
|
Term
| The pars distalis comprises the (posterior/anterior) pituitary |
|
Definition
|
|
Term
| What regulates the secretion of ACTH? |
|
Definition
|
|
Term
| What does somatostatin do? |
|
Definition
|
|
Term
|
Definition
|
|
Term
| What does DOPA (dopamine) do? |
|
Definition
| inhibits prolactin secretion |
|
|
Term
| What does SAL (salsolinol) do? |
|
Definition
| stimulates prolactin secretion in ruminants |
|
|
Term
| What regulates secretion of MSH (melanocyte stimulating hormone)? |
|
Definition
| MIF inhibits, MRF stimulates |
|
|
Term
| What are the 3 "families" of anterior pituitary hormones? |
|
Definition
POMC (peptides)
Somatomammotropic (proteins)
Glycoproteins |
|
|
Term
| What hormones make up the POMC family? |
|
Definition
ACTH
MSH
End (beta endorphin
Enk (enkephalin) |
|
|
Term
| What hormones make up the somatomammotropic family? |
|
Definition
|
|
Term
| What hormones make up the glycoprotein family? |
|
Definition
|
|
Term
| What hypothalamic nuclei are responsible for oxytocin? |
|
Definition
|
|
Term
| What hypothalamic nuclei are responsible for ADH? |
|
Definition
|
|
Term
| Which cells of the pars distalis are basophils? |
|
Definition
thyrotropes
corticotropes
gonadotrophs |
|
|
Term
| Where are magnocellular neurons found |
|
Definition
|
|
Term
| What cells of the pars distalis are acidophils? |
|
Definition
|
|
Term
| What does the MC1-R receptor do? |
|
Definition
| Found within melanocytes, MC1-R is the receptor for MSH-R to promote melanin production & cell proliferation |
|
|
Term
| What does the MC2-R receptor do? |
|
Definition
| Primary receptor for ACTH-R, stimulates glucocorticoid production in the adrenal cortex and lipolysis in adipocytes |
|
|
Term
| What does the MC3-R receptor do? |
|
Definition
| regulation of hypothermia, bradycardia, hypotension |
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