CHARACTERIZATION OF ANTISERA AGAINST BOVINE PROLACTIN FOR INVIVO STUDIES ON PROLACTIN FUNCTION IN THE RAT

  • 1 January 1980
    • journal article
    • research article
    • Vol. 41  (1) , 55-62
Abstract
The Ig[immunoglobulin]G fraction of rabbit antisera to bovine prolactin (PRL), intended for in vivo studies on the role of PRL in the rat, was prepared and characterized in vitro and in vivo. The antibodies showed a strong reaction with bovine PRL in double diffusion, immunoelectrophoresis, radioimmunoassay and passive hemagglutination using bovine PRL-coated erythrocytes. In indirect immunofluorescence on paraffin sections of bovine pituitary glands, the antibodies could be used for the detection of PRL-producing cells. Cross-reaction with rat PRL was observed in passive hemagglutination with rat PRL-coated erythrocytes and in indirect immunofluorescence on rat pituitary gland, but not in any of the other test systems. The ability of the antibodies to neutralize homologous, i.e., bovine, PRL was tested in lactating rats depleted of endogenous PRL by bromoergocriptine treatment. The impaired lactation performance of such animals can be restored by substitution with bovine PRL. If the bovine PRL used for substitution was complexed with anti-bovine PRL-IgG, it lost its biological activity. Injections of even high amounts of the antibodies into lactating rats failed to reveal any effect on lactation. Either the antibodies do not cross-react with circulating rat PRL in contrast to pituitary PRL (preprolactin?) or the cross-reacting antibody-population(s) lack(s) the ability to neutralize the biological function of rat PRL.