(A, B) Zucker lean rats were fed with VAD and VAS diet for 9 weeks. (C) Different categories of VA status were produced by feeding rats with one of four diets: VAD, VAM, VA-Ad and VA-Sup. (D) VAD rats received a single intraperitoneal administration of 100 μg of RA. Individual VAD rat livers were collected for analysis at the indicated time points. The results are presented as − ΔCt [−ΔCt = (Ct of 36B4) − (Ct of Gck )] for mRNA and m-units/mg of GK enzyme activity. Total RNA was isolated from individual rat livers (a > b; c > e, f; and d > f, all P < 0.02). Animal number, n, per group is shown in parentheses.