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An In Vivo Estrogen Deficiency Mouse Model for Screening Exogenous Estrogen Treatments of Cardiovascular Dysfunction After Menopause
Published on: August 13, 2019
Effect of ovariectomy on oestrogen-sensitive feedback elements
Abstract:
Serum LH and FSH were determined by radioimmunoassay in untreated and oestrogen-treated ovariectomized rats. The animals were sacrificed 7, 14, 21 and 28 days after ovariectomy. Oestradiol benzoate was administered in the daily dose of 50 mug on the 2 days preceeding sacrifice. It has been found that oestrogens exert a strong inhibitory effect on the release of LH, as evidenced by a decrease in serum titers of the hormone. Oestradiol suppressed LH almost completely in animals with both low (7 or 14 days post-ovariectomy), and high levels of serum LH(21 or 28 days post-ovariectomy). Oestradiol failed to totally suppress serum FSH at any post-castration time considered. Moreover, the inhibitory effect of oestradiol on FSH release decreased as post-castration time increased. These data suggest that the feedback mechanisms which control the secretion of LH and those which control the secretion of FSH are substantially different.
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