The blunting of the thyrotropin response to repeated thyrotropin-releasing hormone administration is reduced by dopaminergic blockade both at normal and elevated serum levels of thyroid hormones
Fifteen premenopausal women were investigated in the follicular phase of the menstrual cycle with two TRH tests within an interval of 48 to 96 h. Ninety min before each TRH test either 10 mg metoclopramide or saline was injected iv in randomized order. The same procedure was repeated in the following menstrual cycle after pretreatment with T4 (0.5 mg daily for 6-14 days). At least 2 months later t
