tokens: Estrogen pretreated castrated males also showed no change in myocardial blood flow after 17 beta - estradiol , but coronary flow velocity decreased ( P < 0 . 05 ) compared with baseline 1 h after the 200 ng / kg dose ( from 1 . 69 + / - 0 . 61 to 1 . 41 + / - 0 . 42 kHz ) and diastolic coronary resistance increased significantly ( P < 0 . 01 ) compared with control at this time ( 51 + / - 15 compared with 39 + / - 14 mmHg / mkHz ) .