Use of steroid biosynthesis inhibitors to suppress estrogen production is a logical strategy in the treatment of women with hormone-dependent breast cancer. The clinical availability of aminoglutethimide as an inhibitor of cytochrome P-450-mediated steroid hydroxylations prompted study of the precise pharmacological and biochemical effects of this drug. Pharmacokinetic studies revealed that ami...

Inhibitors of steroid sulfatase are being developed as a novel therapy for hormone-dependent breast cancer in postmenopausal women. Data suggest that steroid sulfatase (STS) activity is much higher than aromatase activity in breast tumors and high levels of STS mRNA expression in tumors are associated with a poor prognosis. STS hydrolyzes steroid sulfates, such as estrone sulfate and dehydroepi...

................................................................................................................................. 5 LIST OF ORIGINAL COMMUNICATIONS........................................................................... 11 ABBREVIATIONS ..................................................................................................................... 13 INTRODUCTION...........

Aromatase is a key enzyme in intratumoral estrogen production required for the production of estrogens through the conversion of serum androgens in postmenopausal breast cancer patients. There have been, however, controversies regarding the intratumoral localization of aromatase in human breast carcinoma tissues. Therefore, we have first examined the intratumoral localization of aromatase mRNA/...

background most patients with trauma experience different levels of pain. due to side effects as well as economic burden of drugs used for pain relief after trauma commonly, it is important to use low-cost methods independently or combined with drugs to alleviate pain. objectives therefore, this study aimed to investigate the effects of topical sesame oil on pain severity and frequency of recei...

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. ...

Adult African clawed frogs (Xenopus laevis) were collected from a corn-growing region (CGR) and a non-corn-growing region (NCGR) with different exposure profiles for atrazine and related triazines. Physical, chemical, and biological parameters from the catchment areas were also measured. Frogs were surveyed for possible effects of exposure to triazine herbicides on plasma testosterone (T) and e...

Cytochrome P450 aromatase (CYP19) plays an important role in steroid homoeostasis by converting androgens to estrogens. To evaluate the effects of benzo(a)pyrene (BaP), a model carcinogenic PAH and AhR ligand, on aromatase mRNA expression and enzyme activity, adult Fundulus were exposed to water-borne BaP (1 and 10 microg/L) for 15 days, and embryos were exposed to 10 microg/L for 10 days. Effe...

Castrated male quail display intense male-typical copulatory behavior in response to exogenous testosterone but ovariectomized females do not. The behavior of males is largely mediated by the central aromatization of testosterone into estradiol. The lack of behavioral response in females could result from a lower rate of aromatization. This is probably not the case because although the enzymati...

There is increasing concern that certain chemicals in the environment can cause endocrine disruption in exposed humans and wildlife. Investigations of potential effects on endocrine function have been limited mainly to interactions with hormone receptors. A need exists for the development of alternate in vitro methods to evaluate chemicals for their potential to disturb various endocrine functi...