[Estrogen substitution: effects on lipid, eicosanoid and collagen metabolism in menopause]

Biochemical markers of bone metabolism are not well established as diagnostic tools. Recently, a new radioimmunoassay has been described, that specifically detects the carboxyterminal telopeptide of type I collagen (ICTP). We have used this method in our studies. Ten menopausal women, age 49-64, received 1.25 mg conjugated estrogens (Presomen) within three cycles of 20 days and 8 days pause. Before and under therapy following parameters have been estimated: cholesterol, LDL, HDL, triglycerides, estradiol, FSH, prolactin, thromboxane B2- 6-ketoprostaglandin F1 alpha, ICTP, and the carboxyterminal propeptide of type I procollagen (PICP). Administration of Presomen resulted in significantly increased levels of HDL. Hormonal replacement therapy (HRT) also resulted in significantly decreased levels of cholesterol, LDL, triglycerides, FSH, prolactin, ICTP, and thromboxane B2. PICP and 6-ketoprostaglandin F1 alpha were uneffected by HRT. Our studies confirm the favorable effects of HRT on lipoprotein metabolism. In addition to these findings we noted a beneficial effect on the arachidonic acid metabolism and on the bone resorption, this requires confirmation in clinical trials.