1. at receptor antagonists u 1-2 O, receptor antagonists 口 prazosin(哌唑嗪), for hypertension treatment tamsulosin(坦洛新), for benign prostatic hypertrophy o 1-3 a, receptor antagonists yohimbine(育亨宾)1-2 1 receptor antagonists prazosin（哌唑嗪）, for hypertension treatment tamsulosin（坦洛新）, for benign prostatic hypertrophy 1-3 2 receptor antagonists yohimbine（育亨宾） 1.  receptor antagonists