下列何種受體在交感神經末梢被活化後,會促進正腎上腺素的釋放?
\mathrm{\alpha}_{2}
\mathrm{\beta}_{2}
Dopamine \mathrm{D}_{2}
\mathrm{D}_{2}
Muscarinic \mathrm{M}_{2}
\mathrm{M}_{2}