The aromatase inhibitor, fadrozole, was applied to common carp and goldfish in order to examine its ability to increase the spontaneous and sGnRHa stimulated LH secretion. First, trials in goldfish in 2003 showed fadrozole's moderate ability to potentiate sGnRHa-stimulated LH secretion. However, this ability was much weaker than that obtained with dopamine antagonist, pimozide. There was no ovu...

Teleost fish represent unique models to study the role of neuroestrogens because of the extremely high activity of brain aromatase (AroB; the product of cyp19a1b). Aromatase respectively converts androstenedione and testosterone to estrone and 17beta-estradiol (E2). Specific inhibition of aromatase activity by fadrozole has been shown to impair estrogen production and influence neuroendocrine a...

Mechanical or anoxic/ischemic brain insult results in reactive gliosis and a pronounced wave of apoptotic secondary degeneration (WSD). Reactive glia express aromatase (estrogen synthase) and glial estrogen synthesis decreases apoptosis and the volume of degeneration. Whether aromatization by glia affects gliosis itself or the initiation/maintenance of the WSD remains unknown. Adult male zebra ...

The objective of the present work was to study the effect of a nonsteroidal aromatase inhibitor (fadrozole) on proliferation, estradiol production, aromatase expression and telomerase activity (TA) in pig granulosa cells (GC) from small (1–2 mm) and large (5–7 mm) follicles. The cells were treated with fadrozole for 48 h and 72 h in basal and FSH-stimulated conditions. Fadrozole caused a decrea...

As part of a research effort examining system-wide responses of the hypothalamic-pituitary-gonadal (HPG) axis in fish to endocrine-active chemicals (EACs) with different modes of action, zebrafish (Danio rerio) were exposed to 25 or 100 microg/L of the aromatase inhibitor fadrozole for 24, 48, or 96 h. Global transcriptional response in brain and ovarian tissue of fish exposed to 25 microg/L of...

Cytochrome P450 aromatase (CYP19) is a key enzyme in vertebrate steroidogenesis, catalyzing the conversion of C19 androgens to C18 estrogens such as beta-estradiol (E2). The objective of this study was to assess effects of the CYP19 inhibitor fadrozole on fathead minnow (Pimephales promelas) reproductive endocrinology and physiology in a short-term reproduction assay proposed for identifying sp...

In previous studies we demonstrated the immunohistochemical expression of aromatase in pituitary cells. In order to determine whether pituitary aromatase is involved in the paracrine regulation of prolactin-producing pituitary cells and the physiological relevance of pituitary aromatase in the control of these cells, an in vivo and in vitro immunocytochemical and morphometric study of prolactin...

spectrophotometric and electrochemical studies were successfully used in quantitative analysis of amitriptyline hydrochloride (ath) and nortriptyline hydrochloride (nth). conductometric titration were carried out in equeous solution using iodide and dopamine and serotonine as titrant. two new methods using spectrophotometry are dascribed for the determination of (ath) and (nth) with potassium b...

Pleurodeles waltl is a newt with a ZZ male-ZW female sex determination mechanism, and a temperature-sensitive gonadal sex differentiation. Raising larvae at 32 degrees C from stage 42 to stage 54 (thermosensitive period) drives genetic females to differentiate into functional males. Estrogens are intimately linked with temperature action in this species, as well as in other vertebrates with tem...