Expression of corticotropin-releasing factor (CRF) in peritoneum and pericardium in the rat embryo by in situ hybridization histochemistry

Corticotropin releasing factor (CRF) mRNA expression in the thorax and abdomen was studied by in situ hybridization in rat tissue sections obtained from embryonic day 11 (E12) to E16. On E12 no signal was observed in any region. On E13 the first signals were detected particularly in serous membranes such as pericardium and peritoneum. By E14, the signal was strong in these membranes. On E15 the signal markedly diminished, and on E16 no signal was evident in serous membranes. This stage-specific expression of CRF mRNA in developing pericardium and peritoneum suggests that this peptide acts in pericardial and peritoneal development. (C) 1997 Elsevier Science Inc.