Calbindin D-28k and parvalbumin immunohistochemistry in developing rat retina.

The developmental profiles of two calcium-binding proteins, calbindin-D28k (CaBP) and parvalbumin (PV), were investigated immunohistochemically in the developing rat retina. CaBP-immunoreactivity appeared first on embryonic day 17 in the horizontal, amacrine and ganglion cells; on embryonic day 21 in the inner plexiform layer; and on post-natal day 6 in the outer plexiform layer. The reaction intensity had increased to its maximum level by post-natal day 10. PV-immunoreactivity was first noted on embryonic day 19 in the amacrine and ganglion cells and reached its maximum on post-natal day 10. Two distinct subpopulations of amacrine cells were clearly recognized after post-natal day 6; one was positive for CaBP and the other for PV. Some morphological differences were noted between the two.