Action of adranaline is reversed by prazosine but not by propranol

i.e. (Urinary symptoms of BHP): (133-KDT 6th)* Prazocine is a1 blocker and propranol is non selective beta blocker* Urinary symptoms in BHP are solely due to alpha receptorsThe a blockers have no effect on adrenergically induced cardiac stimulation, bronchial dilatation, vasodilation and most of the metabolic changes because these are mediated predominantly through b-receptors (133-KDT 6th)