Circadian alterations in the clock-related genes by ENF under isocaloric conditions. Liver and epididymal fat samples were collected at ZT 0, 4, 8, 12, 16 and 20 after 4 days of treatment. The gene expression levels of brain and muscle arnt-like protein-1 (Bmal1), circadian locomotor output cycles kaput (Clock), period1 (Per1), period2 (Per 2), cryptochrome-1 (Cry1), cryptochrome-2 (Cry2), D-site of albumin promoter binding protein (Dpp) and Rev-erba under isocaloric diets were estimated by RT-PCR. The relative levels (IC control = 1) were further normalized to 18S RNA levels. The values are expressed as the mean +/- SEM (n = 6 per time point).