Endocrine Flashcards
What are the 3 chemical classes of hormones?
Steroids
Peptides
Biogenic Amines
Name 8 steroid hormones
Aldosterone (mineralocorticoid)renal cortex Z. Glomerulosa)
Androgens (ex: DHEA, renal cortex Z. Reticularis)
Calcitriol (made from calcidiol in kidneys)
Corticosterone
Cortisol (glucocorticoid; renal cortex Z. Fasciculata)
Estrogens
Progesterone
Testosterone
Steroid hormones are:
A. Lipid soluble and pass through plasma membrane
B. Water-soluble and use external cell receptors to enter cell
A. Lipid soluble
Name the 3 types of peptide hormones
Oligopeptides
Polypeptides
Glycoprotiens
Oligopeptides are 3-10aa long. Name 2 of them and where they are released
Oxytocin and Anti-diuretic Hormone (ADH)
Posterior pituitary
Polypeptides are 14-199aa long. Name 2 of them and the function of each
Insulin: lower BGL
Glucagon: increase BGL
Name the 2 glycoproteins
FSH, TSH
Peptide hormones are:
A: Water soluble
B: lipid soluble
A. Water soluble
Biogenic amines are:
A. Lipid soluble
B. Water soluble
B. Water soluble (except thyroid hormone TH)
Name the 4 water soluble monoamines and the 1 that isn’t
Water soluble: Dopamine Epinephrine Norepinephrine Melatonin
Non-water soluble Thyroid Hormone (TH)
Releasing hormones (& inhibiting hormones) are produced in neurons in the hypothalamus. They are stored in vesicles inside the cells until they are released. What does this suggest about the chemical nature of releasing hormones? A. They’re most likely cabs B. They’re most likely nucleic acids C. They’re most likely steroids D. They’re most likely peptides
D. Peptides because they’re water soluble (stored in vesicles)
Local hormones are not circulated in the blood, but rather act on the releasing cell, which are called _______, or neighboring cells, which are called ________.
Autocrine
Paracrine
The main group of local hormones are called what?
Eicosanoids
Eicosanoids, the main group of local hormones, are derived from what acid?
Arachadonic acid, a 20 carbon fatty acid cleaved from phospholipid membrane
Name the 3 groups of eicosanoid local hormones
Prostaglandins
Thromboxanes
Leukotrienes
What are prostaglandins?
Local eicosanoid hormones that can act as autocrine or paracrine.
Differ from endocrine hormones in that they are made throughout the body instead of just one place.
Vasodilator part of inflammation
Inhibit platelet aggregation
What are thromboxanes?
Local hormones of 20 carbon arachadonic acid
Vasoconstrict
Aid in platelet aggregation
What are leukotrienes?
20 carbon arachadonic acid eicosanoid local hormone
Made in leukocytes
Can be autocrine or paracrine
Usually accompanied by production of histamines and prostaglandins during inflammation
Trigger constriction of bronchioles and are major contributor to asthma and allergic rhinitis
Steroid hormones are bound to _______ _________ during transportation in the blood so they don’t act everywhere in the body.
Carrier protein
Steroid hormones enter the cell directly through the _______ __________.
Lipid membrane
________ hormones have to enter the cell, change the machinery, and then produce a product. They stay in the cell for ________ periods of time in contrast to water-soluble hormones.
Steroid
Longer
Do water soluble hormones enter the cell through :
A. the lipid membrane
B. Binding to membrane protein receptors
B. Binding to membrane protein receptors
Once a water soluble hormone binds the membrane receptor protein, a GTP binds, becomes GDP, and activates a ___ protein.
G protein
Path 1: The activated G protein goes to what enzyme bound to the cell membrane?
Adenylate cyclase
Activated G protein binds to adenylate cyclase, which turns ATP into
_________ ______.
Cyclic AMP or cAMP (2nd messenger)
- cAMP binds to and activates a
__________ kinase.
Protein
Path 2: The activated G protein goes to what enzyme?
Phospholipase C
Phospholipase C converts PIP2 into what two things?
IP3
DAG
2nd messenger IP3 can bind to endoplasmic reticulum, which causes the release of what?
Calcium (Ca 2+)
-cAMP can bind to ion channels which allows ____ to flow down concentration gradient into cell.
Ca2+
The released calcium from the binding of IP3 to the endoplasmic reticulum (sarcoplasmic reticulum in muscle cells), along with DAG, activate Protein Kinase C, which does what?
Adds phosphates to target proteins, which cause cellular responses
Calmodulin is activated once _____ binds to it, causing further downstream cellular responses, such as activating protein kinases.
Calcium
The benefit of water soluble hormones is that you already have the cellular machinery; it’s just a matter of turning it on. This is faster than _____soluble hormones.
Lipid
What makes a cell a target of a particular hormone?
The presence of a receptor for that particular hormone for water soluble hormones
For steroid hormones, it depends on the carrier protein that releases at specific effector organ cells
Protein hormones use the
______ _________ pathway, regulating existing enzymes, while steroid hormones influence _______ _________, creating new enzymes.
2nd messenger
Gene expression
Protein hormones act ______ while steroid hormones act ______.
Quickly
Slowly
Protein hormones longevity of effect is _______ while steroid hormone longevity of effect is more ___________.
Temporary
Permanent
Which hormone requires a carrier protein?
A. Protein
B. Steroid
B. Steroid
Hydrophilic hormones require a transport protein to travel in blood.
A. True
B. False
B. False
Many hormones follow a __________ rhythm.
Circadian
Removal of hormone from the blood is usually via the _____ or _______.
Liver
Kidneys
Half-life of each hormone varies and increases due to what?
Where it’s binding
Cells _______ receptors in response to reduced hormone concentration in the blood.
Up-regulate
Cells ________ receptors in response to elevated hormone concentration in the blood.
Down-regulate
Name the 3 different hormone interaction effects
Synergistic
Permissive
Antagonistic
Explain synergistic hormone interactions and provide example
Hormones work together to produce greater effect
Ex: epi and glucagon
Explain permissive hormone interactions and provide example
First hormone allows action of second hormone
Ex: Thyroid Hormone (TH) and epinephrine
Explain antagonistic hormone interactions and provide an example
One hormone causes opposite effect of another hormone
Ex: insulin/glucagon
The hypothalamus is directly connected to the __________ pituitary.
Posterior
The anterior pit is also known as the ____________, and the posterior pit is also known as the ___________.
Adenohypophysis
Neurohypophysis
The _____________-__________ portal system uses blood to transport hormones from the hypothalamus to the anterior pituitary.
Hypothalamo-hypophyseal
Name the 5 releasing hormones released from the hypothalamus to the anterior pituitary
TRH (thyrotropin releasing hormone) PRH (prolactin releasing hormone) GnRH (gonadotropin releasing hormone) CRH (corticotropin releasinghormone) GHRH (Growth hormone releasing hormone)
What does “-trophic” or “-tropic” mean?
Stimulating the activity of another endocrine gland
TRH (thyrotropin releasing hormone) stimulates the ant pit to release what?
TSH (Thyroid Stimulating hormone)
TSH from the ant pit stimulates the thyroid to release what?
TH thyroid hormone