A 33-year-old patient with septic shock is noted to have persistent hypotension despite IV dopamine infusion. The patient is treated with an IV infusion of epinephrine. With which adrenoceptor does epinephrine act to constrict vascular smooth muscle
a1 -Adrenoceptors a2 -Adrenoceptors b1 -Adrenoceptors b2 -Adrenoceptors