Oestrogen replacement therapy after hysterectomy.

OBJECTIVE--To identify those women who might benefit from oestrogen replacement after hysterectomy. DESIGN--Targeted health screening. SETTING--Large group practice. SUBJECTS--All women aged under 50 who had had a hysterectomy. MAIN OUTCOME MEASURES--Concentration of follicle stimulating hormone, symptom profile, uptake of oestrogen replacement therapy. RESULTS--145 of 1953 women aged 32-49 had had a hysterectomy. 35 of the 41 with bilateral oophorectomy and 27 of 104 with one or more ovaries conserved were taking oestrogen replacement. 62 of the 68 who had ovaries conserved and were not taking oestrogen replacement attended for review, of whom 14 had a follicle stimulating hormone concentration > or = 20 IU/l. 16 of the 19 women identified as potentially able to benefit from oestrogen replacement started treatment and were still on treatment at six months of follow up. CONCLUSION--Systematic review of women who had had a hysterectomy identified an important group who would potentially benefit from oestrogen replacement therapy.     

Effect of long term hormone replacement on plasma prolactin concentrations in women after oophorectomy.

Plasma prolactin concentrations were studied in 88 oophorectomised women who had been receiving mestranol or placebo for three to 11 years. Thirty one of them were also studied under basal conditions and by tests with thyrotrophin releasing hormone. Under basal conditions the mean prolactin concentration was higher in the oestrogen treated group but under non-rested, clinic conditions the difference was lost because of a rise in prolactin value in the placebo group only. Hence the groups showed a different prolactin response to the mild stress of clinic attendance but the same proportionate responsiveness to thyrotrophin releasing hormone. The data suggest that long term hormone replacement has no significant effect on circulating prolactin concentrations under non-rested, everyday conditions and that the prolactin stimulating effects of minor stress and oestrogen may share a similar mechanism.     

Hormone replacement therapy.

Hormone replacement therapy is increasingly being used for purposes unrelated to the alleviation of menopausal symptoms, such as the prevention of osteoporosis and cardiovascular disease. Clinical trials, however, suggest that the one drug/many purposes concept may be too optimistic. The availability of new estrogen-like compounds and the discovery of a second estrogen receptor have opened new possibilities for more specific drug development.     

Hormone replacement therapy and cardiovascular disease.

A large amount of research continues to be conducted on the mechanisms of hormone replacement therapy (HRT) effects, and the first of the large clinical trials published its results during the past year. In addition to the well known effects on LDL-cholesterol, HDL-cholesterol, and triglycerides, recent studies confirmed that estrogen with or without a progestin lowers lipoprotein (a) concentrations in women (but not in men). In men, estrogen appears to have a similar effect on other lipids and lipoproteins and on plasminogen activator inhibitor-1 as in women. A comparison of estrogen with simvastatin indicated that simvastatin is better at lowering LDL-cholesterol while estrogen is better at raising HDL-cholesterol; when given in combination the additional effects were modest. Estrogen and simvastatin had similar beneficial effects on endothelial function. The estrogen effect on endothelial function may be blocked by medroxyprogesterone, but the data are inconsistent. These studies of intermediate outcomes were put in perspective by the results of a landmark secondary prevention trial of coronary heart disease (CHD). This randomized placebo-controlled trial (Heart and Estrogen/Progestin Replacement Study) of conjugated equine estrogens plus medroxyprogesterone failed to show the anticipated reduction in CHD, and at the same time the threefold increase in venous thromboembolism confirmed that HRT is procoagulant. Therefore, it is still not known whether HRT is a viable option for the prevention of CHD. The preliminary data on selective estrogen receptor modulators are not overly promising, but a definitive trial to test whether raloxifene will reduce CHD is ongoing.     

Uterine tube microvascular architecture after oophorectomy in the rabbit

The oxytocin and vasopressin nerve fibers in the intra- and extrahypothalamic neuronal systems of several mammalian brains are immunohistochemically demonstrated using a modified peroxidase-antiperoxidase technique. The axonal processes of these peptidergic neurons are classified into thick and thin beaded fibers. Thick beaded fibers were preferentially distributed in the hypothalamo-neurohypophysial tract and in some circumventricular organs, with termination on the blood vessels. Thin beaded fibers were found in various extrahypothalamic areas and these terminals were in the vicinity of the neuronal somata of such areas. This report suggests that there are at least two different functions concerning neurotransmission in the oxytocin and vasopressin neuronal system.