Cell- and stage-specific expression of basic FGF in the developing rat gonads.

Abstract

In order to clarify the participation of basic fibroblast growth factor (bFGF) in rat gonadal differentiation and development, immunohistochemical localizations of bFGF were chronologically studied in Sprague-Dawley rat gonads from gestational day (GD) 13 to postnatal day (PD) 21 by using avidin-biotin complex technique. Immunohistochemical reactivity to bFGF antibody was positive in the germ cells. Slight or moderate immunostaining was seen in male germ cells from GD 18 to PD 5, and in female germ cells from PD 5 to 21. Leydig/interstitial cells in male gonads were slightly or moderately stained from GD 16 to PD 21. On the other hand, other types of gonadal cells were not stained during the perinatal period. These results indicate that bFGF shows discrete cell- and stage-specific patterns of expression in gonads during the perinatal period and is likely to participate in control of gonadal development in rats.