Injection of steroid-free bovine follicular fluid (bFF; 2 \m=x\5 ml s.c. 12h apart) into anoestrous ewes lowered plasma FSH concentrations by 70% and after 24 h had significantly (P < 0\m=.\01)reduced the number of non-atretic follicles (\m=ge\1 mm diam.) without influencing the total number of follicles (\m=ge\1 mm diam.) compared to untreated controls. Hourly injections of FSH (10 \g=m\gi.v. ...

Aromatase is the enzyme that converts androgen to estrogen. Our laboratory has proposed and demonstrated that aromatase is an important target of some environmental chemicals. We have found that some of these compounds inhibit aromatase activity, resulting in a decrease in the level of estrogen or an increase in the level of androgen in cells. Environmental chemicals can also modify the express...

The effects of two steroidal (4-hydroxyandrostenedione and atamestane) and three non-steroidal (fadrozole, vorozole, and pentrozole) aromatase inhibitors on the levels of aromatase mRNA and protein were examined in vitro and in vivo. Immunocytochemistry revealed increased quantities of immunoreactive aromatase in human choriocarcinoma-derived JEG-3 cells in response to pretreatment with the non...

The strategy of using estrogen suppression to treat breast cancer led to the development of aromatase inhibitors, including the third-generation nonsteroidal compounds anastrozole and letrozole, and the steroidal compound exemestane. Aromatase inhibitors potently inhibit aromatase activity and also suppress estrogen levels in plasma and tissue. In clinical studies in postmenopausal women with b...

Aromatase inhibitors have been widely used for the endocrine treatment of estrogen-dependent breast cancer in postmenopausal patients. However, clinicopathological studies of aromatase have been limited due to unsatisfactory specificity and/or restricted availability of anti-aromatase antibodies. Here, we have generated a polyclonal antiserum with high affinity and specificity for human aromata...

BACKGROUND Several chemicals in the environment have the potential to inhibit aromatase, an enzyme critical to estrogen synthesis. OBJECTIVES The objective of this study was to provide a detailed characterization of molecular and biochemical responses of female fathead minnows to a model aromatase inhibitor, fadrozole (FAD). METHODS Fish were exposed via water to 0, 3, or 30 microg FAD/L fo...

Fish present daily and seasonal rhythms in spawning and plasmatic levels of steroids that control reproduction. However, the existence of the rhythms of expression of the genes that underlie the endocrine mechanisms responsible for processes such as steroidogenesis and reproduction in fish have still been poorly explored to date. Here we investigated the daily pattern of the expression of key g...

The role of estrogens is dual: they suppress basal expression of gonadotropins and enhance GnRH responsiveness at the time of the LH surge. Estrogens are synthesized by cytochrome P450 aromatase (P450arom), encoded by the cyp19 gene. We focused on the cyp19 gene in rat and showed that it is expressed in gonadotropes through promoters PII and PI.f, using RT-PCR and dual fluorescence labeling wit...

background: endometriosis is the presence of endometrial glandular and stromal cells outside of the uterine cavity. our previous study showed that in vitro culture of human endometrial tissue in a three-dimensional (3d) fibrin matrix could mimic the early stages of endometriosis with invasion gland and stroma formation and sprouting of new vessels. objective: the objective of the present study ...

Immunohistochemistry is one of the most suitable methods for the detection of intratumoral aromatase in order to identify patients who may respond to aromatase inhibitor therapy in hormone-dependent breast cancer. Previous studies showed statistically significant correlation between results of immnuohistochemistry and biochemical analysis in carcinoma components stained by aromatase monoclonal ...