Mechanisms of cardiovascular activity of ovarian hormones

The present article focuses on the effects of the ovarian steroids, particu larly oestrogens, on the cardiovascular system. It reviews recent advances regarding the mechanisms of action of these hormones on vasomotor tone and on vascular cell growth and proliferation. The consensus of the published d ata is that oestrogens, through their direct or genomic-dependent activitie s, elicit beneficial effects on mechanisms which control blood flow and cha nges that occur during plaque formation. These findings seem to contribute to understanding oestrogen cardioprotection and also raise awareness of a v ariety of clinical conditions in which oestrogen treatment could be indicat ed because of its effects on blood circulation. The effects ts of progestins on the cardiovascular system are less well stu died. These hormones, which have to be added to oestrogens to protect again st the unwanted side-effect of endometrial hyperplasia, have a number of po tential adverse effects: they reduce HDL lipoproteins and attenuate blood f low and arterial size and compliance. Although current areas of controversy include the effects of progestin administration on the cardioprotective as pects of oestrogen therapy, increasing evidence suggests that progestins co uld have either neutral or opposing effects versus oestrogens depending on their dose and androgenicity. The final section of his article summarizes t he clinical experiences on the use of oestrogens, administered alone or in a combined scheme, in postmenopausal women with coronary atherosclerosis, e ffort angina, microvascular angina and arterial hypertension.