Effects of Rathke's Pouch Mesenchymal Cells on Growth Hormone and Prolactin Release from Pituitary Clonal Cells (2E6) 1

Summary

2E6 clonal cells were cultured with (a) mesenchymal cells derived from Rathke's pouch and the surrounding tissue from fetal rats of 11–13 days gestation, (b) skin fibroblast cells derived from loose connective tissue under the skin of 1- to 5-day postnatal rats, (c) conditioned medium taken from a culture of these Rathke's mesenchymal cells and diluted to 10%, 20%, and 30% with growth medium, and (d) conditioned medium taken from a culture of skin fibroblast cells and diluted to 10%, 20%, and 30% with growth medium. Radioimmunoassay of the media from these cultures revealed an increase in both GH and PRL secretion in the cultures containing 2E6 cells and Rathke's mesenchymal cells and 2E6 cells grown in conditioned media from the Rathke's mesenchymal cells. However, the cultures of 2E6 and skin fibroblasts or its conditioned media showed no increase in hormonal secretion. Rathke's pouch and surrounding mesenchymal cells and its conditioned media stimulated cell proliferation in the 2E6 clonal cells whereas the skin fibroblasts and their conditioned media did not. We concluded that the mesenchyme of Rathke's pouch and its surrounding tissue secreted a growth factor(s) which stimulated hormonal production and secretion and cell proliferation in pituitary glandular cells.