title: Immunocytochemical identification of the prolactin-secreting cells in the teleost pituitary with an antiserum to chum salmon prolactin.
abstract: An antiserum raised to highly purified chum salmon (Oncorhynchus keta) prolactin (sPRL) was used to identify prolactin-producing cells in the adenohypophysis of 15 species of teleosts by the immunocytochemical peroxidase-antiperoxidase method. In the chum salmon, the only pituitary cells that reacted with sPRL antibody were the PRL cells organized as follicular structures in the rostral pars distalis. When the antiserum was absorbed with sPRL, on the other hand, no immunoreactive cell was observed in the pituitary, indicating the specificity of the antiserum. Furthermore, the antibody to sPRL reacted only with PRL cells in the pituitaries of three species of salmonids, a plecoglossid, eel, carp, goldfish, killifish, tilapia, and five species of marine fishes, thus showing no species specificity of the antibody among the teleosts tested. The PRL cells of the eel decreased in number and also in immunoreactivity after adaptation to seawater for 1 month. On the other hand, highly immunoreactive PRL cells were observed in the pituitaries of marine fishes, although the cells were much fewer in number than in eels and in other fishes in fresh water.
mesh_terms: D000818:Animals; D005399:Fishes / Q000033:anatomy & histology*; D010902:Pituitary Gland / Q000166:cytology* / Q000378:metabolism; D011388:Prolactin / Q000378:metabolism*; D012474:Salmon; D013045:Species Specificity
chemical_list: D011388:Prolactin