The percentage of c-fos positive cells increased in CL and HF-LD rats compared with LD group (CL vs. LD: 20.01 ± 0.01% vs. 13.02 ± 0.10%; HF-LD vs. LD: 44.66 ± 0.01% vs. 13.02 ± 0.105). The gene discussed is FOS; the disease is hydrops fetalis.