Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
15 Cards in this Set
- Front
- Back
|
Hidrosoluble Hormones
Membrane Receptor |
Insuline
Glucagon Catecolamies ADH |
|
|
Lipid Soluble Hormones
Intracelular Receptor |
Steroids
Thyroxine Calcicitriol Retinoic acid |
|
|
What are Protein Kinases?
|
enzymes that phosphorilates many other proteins, changing their activity.
Protein Kinase A,C,G, and Thyrosine Kinase |
|
|
The four Pathways for water soluble Hormones?
|
cAMP
PIP2 cGMP insuline and growth factors |
|
|
What are protein phosphatases?
|
enzymes that Dephosphorilates, many other proteins changing their activity
|
|
|
What are receptor in these pathways coupled through?
|
trimeric G proteins
(membrane Receptors) |
|
|
Subunits of trimeric G proteins?
|
alpha
beta gamma |
|
|
What happens to the G protein when the hormone binds the membrane receptor?
|
Receptor becomes activated and engages the corresponding G protein,
alpha binds GTP, so alpha dissociates from beta and gamma, The activated alpha subunits alters the activity of Adenylcyclase |
|
|
G proteins in inactive form?
|
alpha subunit binds to GDP, and is in complex with beta and gamma.
|
|
|
Is alpha subunit is a s?
|
adenylcyclase is activated
|
|
|
if alpha is 1?
|
adenylcyclase is ihibited?
|
|
|
So How is the trimeric G protein cycle completed
|
after the above steps, the activated GTP, is dephosphorilated in GDP, and alpha will rebind to beta, and gamma, therefore inactive again
|
|
|
Hormones that use the cAMP pathway?
|
Glucagon, epinefrin (beta,alpha2),norepinefrin
|
|
|
Sequence for this pathway?
|
Hormone binds receptor,
Trimeric G protein engaged ( Gs,Gi) Adenylcyclase function altered cAMP concentration altered (Second messenger) Protein Kinase A Phosphorilation of proteins(enzymes, CREB proteins,etc) |
|
|
The epinephrine and the beta 1 receptor sequence?
|
epi binds to receptor in cell membrane,
receptor engages trimeric Gs protein, activated adenylcyclase increases cAMP concentration, activates protein kinase A, Phosphorilation of ligand gated Calcium chanel, chanel opens, calcium inside cardiac musle cell increases, interaction between actin and miosin increases, contractilily increases. |
