Effects of Prolactin on Cultured Splenocytes from Mice

Abstract

Contents: Prolactin (PRL) was purified from human amniotic fluid and further fractionated on ConA Sepharose 4 B. The activities of the retarded migrating glycosylated PRL‐ConA‐S were examined in splenocytes from mice using three different test systems in comparison to PRL‐standard (PRL‐ST). These assays included the conductometrical cytometry for measurement of cell count and volume, the 3H‐thymidine incorporation and the IgG‐expression. The sensitivity of splenocytes ro the PRL‐forms was different in the various assays and dose‐dependent. A small PRL‐ConA‐S dose caused a significant stimulatory effect on the cell count, the 3H‐thymidine proliferation and the cell volume, whereas the IgG‐expression was only nonsignificantly increased in higher concentration. Even in a moderate physiological concentration (0.15 mlU/ml) PRL‐St exterted an inhibitory effect on the cell proliferation which was directly demonstrated by cell counting. The results suggest a different physiological role of PRL‐forms.