Granulated metrial gland cells in the lungs of mice in pregnancy and pseudopregnancy.

A study has been made, using light microscopy, of GMG cells in the lungs of pregnant mice and pseudopregnant mice with deciduomata. GMG cells are found in the lungs from Day 8 to Day 17 of pregnancy and are mainly located in the interalveolar septa. The temporal relationship between GMG cells in the lungs and GMG cells in the blood vessels of the decidua basalis and metrial gland suggests that the GMG cells in the lungs are migrants from the uterus. The presence of GMG cells in the lungs is considered in relation to the possibility that a site of functional importance to this cell type is the labyrinthine placenta. GMG cells are found in the uterine blood vessels and lungs of pseudopregnant mice with deciduomata. This finding suggests that the migration of GMG cells is under the influence of the mother rather than under the control of factors derived from the fetal allograft.