Pituitary steroids in two teleost species: immunohistological and biochemical studies.
Antisera raised against steroid hormones [estradiol-17 beta (E2), testosterone (T), 11 beta-hydroxyandrostenedione (OHA)] were used to localize immunoreactive material in fixed and paraffin-embedded pituitaries of the African catfish and the rainbow trout. Organic extracts of pituitary homogenates were analyzed for steroid hormones by radioimmunoassay and gas chromatography-mass spectrometry (E2 in female catfish only). With the exception of an E2-positive cell type in the catfish neurointermediate lobe, steroid immunoreactivity was found to be restricted to the cytoplasm of adenohypophyseal cells, which were also labeled after incubation with catfish alpha,beta-gonadotropin and salmon gonadotropin antisera, respectively. Steroid levels determined by radioimmunoassay in the catfish ranged between 85 and 628 pg/pituitary, while lower levels (2-8 pg/pituitary) were found in the rainbow trout. E2 was identified by gas chromatography-mass spectrometry at a level of 84 pg/pituitary. The observation that immunolabeling after steroid antiserum incubation is confined mainly to gonadotrops provides morphological evidence for direct steroid effects on this particular cell type.
Peute
J
J
Department of Experimental Zoology, University of Utrecht, The Netherlands.
Schulz
R
R
Glazenburg
K
K
Lambert
J G
JG
Blüm
V
V
D000735:Androstenedione / Q000031:analogs & derivatives* / Q000032:analysis / Q000276:immunology / Q000378:metabolism; D000818:Animals; D000937:Antigen-Antibody Reactions; D002397:Catfishes / Q000378:metabolism*; D004958:Estradiol / Q000032:analysis / Q000276:immunology / Q000378:metabolism*; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D006065:Gonadotropins, Pituitary / Q000276:immunology / Q000378:metabolism; D007150:Immunohistochemistry; D008297:Male; D010902:Pituitary Gland / Q000032:analysis / Q000166:cytology / Q000378:metabolism*; D011863:Radioimmunoassay; D012487:Salmonidae / Q000378:metabolism*; D013739:Testosterone / Q000032:analysis / Q000276:immunology / Q000378:metabolism*; D014337:Trout / Q000378:metabolism*
D006065:Gonadotropins, Pituitary; D013739:Testosterone; D000735:Androstenedione; D004958:Estradiol; C003582:11-hydroxyandrostenedione