Both zinc deficiency and diet restriction decreased kidney total RNA concentration in rats

Abstract

Total RNA concentration in liver is known to be decreased by dietary zinc deficiency. In this study, we have examined whethre zinc deficiency and diet restriction affect total RNA concentration and expression of Actb and Gapdh in kidney. Thirty 3‐week‐old male SD rats were assigned into 3 dietary treatment groups of 10 for the four‐week study: Control group (AIN‐93G), Zn‐deficient group (4.5 mg Zn/kg; ZD) and pair‐fed group (AIN‐93G; PF). Kidney was separated into cortex and medulla for RNA isolation. Real‐time PCR analysis was performed. Difference between groups was statistically analyzed by Fisher's PLSD. P value less than 0.05 was considered significant. Total RNA concentrations in the medulla of ZD and PF were significantly decreased compared with Control. Total RNA concentrations in the cortex of PF was significantly decreased compared with Control. The Gapdh/total RNA ratio in the cortex were increased in PF compared with Control. The Actb/total RNA ratio in the cortex of PF was significantly increased compared with Control, and the Actb/total RNA ratio in the medulla of ZD and PF were significantly increased compared with Control. These results suggest that both zinc deficiency and diet restriction affect total RNA concentration and expression of Gapdh and Actb in kidney. This work was supported by KAKENHI grant‐in‐aid for Research Activity Start‐up (21800073) and Young Scientists (B) (23700928).