[The effect of prolactin on the production of surfactant in rat fetal lung].

The significance of prolactin (PRL) in the production of surfactant in the fetus was investigated by the analysing the phospholipids produced in the lung after PRL administration. 1 mg of ovine PRL was injected into rat fetus. The phospholipids extracted from the fetal lung were analyzed by TLC and GC. Serum corticosterone was measured by RIA. The content of phosphatidylcholine (PC) and dipalmitoylphosphatidylcholine (DPPC) after treatment with PRL was demonstrated to be significantly higher than the control. Production of corticosterone was activated by PRL injection and its serum level reached the maximal value 24 hours after the injection. DSPC in the fetal lung was increased significantly by PRL and its highest content was found 48 hours after the peak of serum corticosterone level. PRL was shown to be involved in the production of surfactant in the fetal lung. Furthermore, the lag time between corticosterone and DSPC production indicated DSPC biosynthesis may be dependent on increased corticosterone after PRL administration.