| Abstrakt: |
In adult female rats, the effects of progesterone (P), norethisterone acetate (NEA), levonorgestrel (LNG), dienogest (DEG) and chlormadinone acetate (CMA) given alone at doses of 2.5 or 10 mg/kg p.o. or in combination with s.c. implanted estradiol (E2) on total cholesterol (TC), high-density-lipoprotein cholesterol (HDL-C), low-density-lipoprotein cholesterol (LDL-C) and very-low-density-lipoprotein cholesterol (VLDL-C) were investigated. Additionally, the lipoprotein pattern was determined using agarose gel electrophoresis. Synthetic gestagens derived from nortestosterone (NEA, LNG, DEG) lowered TC by reduction of HDL-C and LDL-C, whereas E2 induced an increase of these lipids. The decrease of HDL-C and LDL-C caused by the gestagens was also found in E2 pretreated rats. In contrast, the pregnane related CMA and P given alone did not diminish TC, HDL-C or LDL-C. But they partly reversed the enhancing effect of E2 on the HDL-C fraction following their simultaneous administration. The results suggest that the cholesterol lowering effects of gestagens are mediated rather via androgen than via progesterone receptors. |
