The influence of mestranol and chlormadinone given separately or in combination on the effects evoked by a high-fat diet in female rabbits.

: The effect of mestranol and chlormadinone, the hormones contained in oral contraceptives: on lipid metabolism, some hemostatic parameters and on morphology of aorta, liver and heart was tested after separate or combined administration to mongrel female rabbits fed on a normal or high-fat diet (HFD). HFD administration led to typical atheromatous changes in the aortal intima. The hormones given together with HFD attenuated the augmentation of lipid serum level and the extent of atheromatous plaques in the intima. The percent content of alpha-lipoproteins was significantly lower in groups receiving HFD with or without the hormones than in the controls, but it was higher than in controls in the rabbits receiving the hormones alone. Chlormadinone given together with HFD potentiated atheromatous aortal changes, which occurred not only in the intima but also in the media. Mestranol given together with HFD significantly counteracted the development of atheromatous changes. Female rabbits receiving mestranol and chlormadinone displayed a significant increase in fibrinogen content, while those receiving mestranol showed an increased time of fibrinolysis. HFD produced a hepatic damage, which was augmented in rabbits concomitantly receiving the hormones. The hormones alone also displayed some, a less pronounced hepatotoxic action.