gonad. Please refer to our general review". In the past studies on the biosyn thesis, emphasis was laid on the elucidation of production route of sex hormones . The route established to date runs thus : Acetate• ̈cholesterol-, 22-hydroxy cholesterol pregnenolone • ̈ progesterone • ̈17-hydroxy progesterone-• ̈ƒ¢4-and rostene-3, 17-dione• ̈19-hydroxy-ƒ¢4-and rostenedione-,estrone->estradiol-17ƒÀ , but...

Female-female aggression often functions in competition over reproductive or social benefits, but the proximate mechanisms of this apparently adaptive behaviour are not well understood. The sex steroid hormone testosterone (T) and its metabolites are well-established mediators of male-male aggression, and several lines of evidence suggest that T-mediated mechanisms may apply to females as well....

Male and female Chalcides ocellatus were gonadectomized and cold acclimated at 15 degrees for 1 week. Lizards were injected with testosterone and estradiol, and their oxygen consumption was determined at 15 degrees. Testosterone and estradiol caused a significant increase in the whole body rate of oxygen consumption in male and female lizards, respectively.

Although the role of testosterone in the aetiology of social dominance is often suggested, surprisingly few studies have addressed the relationship between sex steroid hormones and dominance as a personality trait. In this paper, the relationship between testosterone and dominance is studied in a sample of adolescent boys and girls, taking into account the moderating role of gender ideology and...

The morphology and physiology of both the vulva and vagina undergo characteristic age-related changes over a lifetime. At birth, these tissues exhibit the effects of residual maternal estrogens. During puberty, the vulva and vagina mature under the influence of adrenal and gonadal steroid hormones. During the reproductive years, the vagina responds to ovarian steroid hormone cycling, and both t...

Effective contraception is necessary in countries where limiting population growth has become a public policy imperative. The main antigenic targets for contraceptive vaccine development can be listed as following: 1) sperm antigens, 2) zona pellucida antigens, 3) gonadotrophin-releasing hormone, 4) chorionic gonadotrophin, 5) other protein/peptide hormones (follicle-stimulating hormone, lutein...

There is considerable evidence from animal studies that the mesolimbic and mesocortical dopamine systems are sensitive to circulating gonadal steroid hormones. Less is known about the influence of estrogen and progesterone on the human reward system. To investigate this directly, we used functional MRI and an event-related monetary reward paradigm to study women with a repeated-measures, counte...

Sex steroids play critical roles in the regulation of the brain and many other organs. Traditionally, researchers have focused on sex steroid signaling that involves travel from the gonads via the circulation to intracellular receptors in target tissues. This classic concept has been challenged, however, by the growing number of cases in which steroids are synthesized locally and act locally wi...