LEP and hydrops fetalis: Further, the slope of regression was much lower in Re-HF group relative to that in Re-LF group (Re-LF, y = 0.1226x + 0.8987, Re-HF, y = 0.0181x + 0.1693, P < 0.01), suggesting that a small increase in leptin expression might result in more notable up-regulation of LEPRb expression in Re-LF group compared to Re-HF group.