Term
| What are the three categories of hormones? |
|
Definition
1. Proteins and peptides - stored in secretory vesicles
2. Tyrosine derivatives - stored in secretory vesicles
3. Steroids - Can not be stored in secretory vesicles |
|
|
Term
| What is Kd and how is it determined? |
|
Definition
It is the concentration of hormone that half saturates teh receptors
Kd = [H][R]/[HR] = k2/k1
Rate of association = k1 [H]/[R]
Rate of dissociation = k2 [HR] |
|
|
Term
| What are the 4 types of G proteins? |
|
Definition
Gs: stimulates adenylyl cyclase
Gi: Inhibits adenylyl cyclase
Gq: Stimulates Phospholipase C
Gt: activates cGMP phosphodiesterase |
|
|
Term
| How is phospholipase C activated, and what are its effectors downstream? |
|
Definition
| It is activated by Gq family of GPCRs. It creates DAG and IP3. IP3 causes release of Ca+2 from intracellular stores |
|
|
Term
|
Definition
| it increases the affinity of PKC for Ca+2, promoting increased PKC activity at resting levels of intercellular Ca+2 |
|
|
Term
|
Definition
| Atrial natriuretic peptide. When ANP binds its receptor, the guanylyl cyclase becomes activated, generating the second messenger cGMP. cGMP activates kinases and phosphodiesterases, which antagonize responses that require cAMP by cleaving cAMP. |
|
|
Term
| What are the two groupings of intracellular receptors? |
|
Definition
1. glucocorticoids, meneralcorticoids, progesterone, androgens
2. estrogen, thyroid hormones, vitamin D3, retinoic acid |
|
|
Term
| What is the structural setup of steroid receptors? |
|
Definition
- DNA binding domain w/ zinc finger
- 2 hormone binding domains and hypervariable region b/t the NH2 tterminus and DNA biding domain |
|
|
Term
| What protein are steroid receptors commonly associated w/? What is its purpose? |
|
Definition
heat shock protein 90 (HSP90)
When bound to HSP90, the receptors can bind hormone but not DNA. Once hormone is bound, HSP90 dissociates |
|
|
