A new panoptic stain for developmental biology--the mouse placenta paradigm.

A panoptic histological stain, PHTA, is introduced for routine use in developmental biology. The protocol is based on three dyes, hematoxylin and, after tannic acid treatment, phloxine B and azure B. It was optimized for differential staining of extracellular matrix, cytoplasm and chromatin. The method is quick, inexpensive and well-reproducible. The mouse placenta is used here to demonstrate the excellent suitability of PHTA for routine morphology.