ESTROGENS REDUCE PLASMA HISTIDINE-RICH GLYCOPROTEIN (HRG) LEVELS IN ADOSE-DEPENDENT WAY

Plasma levels of histidine-rich glycoprotein (HRG) were investigated i n three groups of women receiving a different dose of estrogens. First , the effect of low-dose estrogen was studied in a group of 83 post me nopausal women who were treated with 0.625 mg conjugated estrogens (CE ). No significant change from baseline levels was found at the end of cycle 3 and cycle 13. Secondly, in 15 mothers and 23 daughters using o ral contraceptives (OC) containing 30-50 mu g ethinyl estradiol (EE) d aily the mean HRG level was 14% and 24% lower than in a group of 144 m others and 134 daughters not taking oral contraceptives. respectively (p < 0.05). Finally, in 11 excessively tall prepuberal girls who recei ved 300 mu g EE daily to reduce their final height the mean plasma HRG levels were decreased by 68% (p < 0.005). The effect of progestogens administered during low-dose and high-dose estrogen therapy appeared t o be minor. The results from these three studies indicate that estroge ns reduce plasma HRG levels in a dose-dependent way.