Regulation of androgen receptors in Atlantic croaker brains by testosterone and estradiol.

• A nuclear androgen receptor (AR1), distinctly different from the mammalian AR, has previously been identified in the brain of the Atlantic croaker, Micropogonias undulatus. Interestingly, brain AR1 levels were higher in gonadally recrudesced than in regressed fish. Therefore, the possible involvement of gonadal steroids in the regulation of brain AR1 levels was investigated in the present study. Saturation analysis of [3H]testosterone binding showed that brain AR1 levels were significantly reduced (2-3-fold) in either the nuclear or cytosolic fractions of both males and females three weeks after gonadectomy. Implantation of gonadectomized females with testosterone or estradiol-17beta one week prior to sampling resulted in physiological plasma steroid concentrations and restored brain AR1 levels to 60-105% of those in intact or sham-operated fish. These results suggest that gonadal factors, including both androgens and estrogens, are involved in the physiological regulation of brain androgen receptors in a teleost species during the reproductive cycle.

Subject headings

NATURVETENSKAP  -- Biologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences (hsv//eng)

Keyword

Animals

Brain

physiology

Estradiol

analogs & derivatives

chemistry

metabolism

Female

Hormone Replacement Therapy

Male

Orchiectomy

Ovariectomy

Perciformes

physiology

Receptors

Androgen

metabolism

Receptors

Cytoplasmic and Nuclear

metabolism

Seasons

Sex Characteristics

Testosterone

analogs & derivatives

chemistry

metabolism

Up-Regulation

drug effects

Publication and Content Type

ref (subject category)

art (subject category)