Glycosylated prolactin in the murine pituitary: Detection by a novel assay and alteration of concentrations by physiological and pharmacological stimuli

• Published in: Biochemical and biophysical research communications Vol. 148; no. 1; pp. 505 - 514
• Main Authors: Sinha, Y.N., Jacobsen, B.P.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 14.10.1987
• Subjects: Animals; Bromocriptine - pharmacology; Estradiol - pharmacology; Female; Immunoassay - methods; Lactation; Lectins; Mice; Mice, Inbred Strains; Molecular Weight; Ovariectomy; Perphenazine - pharmacology; Pituitary Gland - drug effects; Pituitary Gland - metabolism; Pregnancy; Progesterone - pharmacology; Prolactin - analogs & derivatives; Prolactin - analysis; Prolactin - metabolism; Rats; Rats, Inbred Strains; Testosterone - pharmacology; PBS; GH; prolactin; SDS; con A; 2-ME; nitrocellulose; concanavalin A; glycosylated PRL; PRL; immunoreactive PRL; phosphate-buffered saline; RIA; IR-PRL; BSA; 2-mercaptoethanol; radioimmunoassay; sodium dodecyl sulfate; G-PRL; growth hormone; NTC; bovine serum albumin
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/0006-291X(87)91140-5

In both rat and mouse pituitary extracts, we detected concanavalin A-binding prolactin immunoreactivity by a lectin-binding radioimmunoassay developed recently. The activity increased in response to estradiol benzoate treatment and lactation, stimuli that augment prolactin secretion, and decreased in response to acute nursing and perphenzine administration, stimuli that cause massive release of prolactin. Western blot analysis revealed a prolactin-immunoreactive band 2,000–3,000 greater in M r than the main prolactin band that bound to 125I-labeled concanavalin A. These results suggest the existence in the murine adenohypophysis of a glycosylated form of prolactin, which seems to be released under certain physiological states.