Teratogenic effects of implanting fibroblast growth factor-2-soaked beads in the cardiac region of the stage 24 chick embryo.

The identification of fibroblast growth factor-2 (FGF-2), and other family members, in a variety of embryonic tissue extracts has implicated these growth factors as participants in many embryonic events, including cardiogenesis. The present study was conducted in an attempt to characterize the effects of exogenous FGF-2 on the development of the avian heart. Heparin acrylic beads, each soaked in 100 micrograms/ml FGF-2, were applied to the Hamburger and Hamilton [(1951) J. Morphol. 88:49-92] stage 24 (day 4 of incubation) chick heart, near the primitive ventricle. The embryos were allowed to develop until stage 41 (day 15), at which time they were observed for the presence of gross external and internal anomalies. Crown rump length (CRL), wet weight (WW), and various heart measurements were obtained and compared. The survival rate of the control group was significantly higher (P < 0.05) than that for the experimental group and the anomaly rate for the control group was significantly lower (P < 0.01) than that for the experimental group. The experimental group exhibited a wide range of anomalies, most of which were cardiac in nature; however, anomalies of the ventral thoracoabdominal wall were also noted. Our data suggest that application of exogenous FGF-2 has teratogenic effects on cardiac development as well as on the development of the ventral body wall of the avian embryo.