title: Developmental immunohistology of melanotrophs in Xenopus laevis tadpoles.
abstract: The adenohypophysial primordium of Xenopus laevis tadpoles at stages 33/34 to 46 (Nieuwkoop and Faber, 1956) were examined immunohistologically for alpha-MSH, beta-MSH and ACTH. beta-MSH was demonstrated from stage 37/38 onwards, and alpha-MSH from stage 39. No signs of ACTH production were detected. alpha-MSH and beta-MSH occurred in the same cells. No differences were found in the intensity of immunofluorescence between tadpoles which were kept on a black and a white background. The present study lends no support to the hypothesis concerning the derivation of alpha-MSH from ACTH. The observations made suggest that the morphological formation of the pars intermedia is accomplished during stages 37/38 to 39.
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000032:analysis; D000818:Animals; D005260:Female; D008297:Male; D009074:Melanocyte-Stimulating Hormones / Q000032:analysis; D010902:Pituitary Gland / Q000196:embryology*; D010903:Pituitary Gland, Anterior / Q000166:cytology / Q000196:embryology*; D013997:Time Factors; D014981:Xenopus / Q000196:embryology*
chemical_list: D000324:Adrenocorticotropic Hormone; D009074:Melanocyte-Stimulating Hormones