Plasma mass of total ROH, RE, and RBP-ROH (A) and brain mass of total ROH and CM- and RBP-derived ROH (B) in control and VA-supplemented rats. The total ROH bars represent the mean ± SEM of 20 rats killed at 5 sampling times from 0 to 8 d after dosing on postnatal day 4. The RE and RBP-ROH bars represent the mean ± SEM of 5 pooled samples from 20 rats killed at 5 sampling times from 0 to 8 d after dosing on postnatal day 4. Values for CM- and RBP-derived ROH in the brain were estimated in WinSAAM version 3.0.8 in a steady-state solution based on the input value of total ROH mass in plasma. *P < 0.05, ***P < 0.001. CM, chylomicron; RBP, retinol-binding protein; RE, retinyl ester; ROH, retinol; VA, vitamin A.