How epinephrine/norepinephrine work on cardiac mysoties themselves
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| STEP 1 |
Binding of epinephrine/norepinephrine changes shape of beta receptor -> activates G-Protein |
| STEP 2 |
G-Protein subunit activates adenylate cyclase |
| STEP 3 |
Adenylate cyclase catalyzes conversion of ATP to cAMP |
| STEP 4 |
cAMP activates protein kinase A |
| STEP 5 |
Protein kinase phosphorylates Calcium channels, influx on calcium in cell, stimulates contraction |
| STEP 6 |
protein kinase also phosphorylates calcium channels on sarcoplasmic reticulum. calcium then moves into the cytoplasm and stimulates contraction. |
| STEP 7 |
Protein kinase phosphorylates myosin, stimulates contraction |
| STEP 8 |
Protein kinase phosphorylates sarcoplasmic Calcium ATPase -> speeds removal of calcium from cytoplasm during relaxtion. decreases over relaxtion time. |
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