REN and chronic kidney disease: For instance, intake of a pea protein hydrolysate (0.5% and 1% of diet) for 8 weeks inhibited renal renin mRNA by about 50% in Han:SPRD-cy rats, a chronic kidney disease model with hypertension.14 Similarly, egg protein-derived peptide, RVPSL, also decreased kidney renin mRNA expression after 4 weeks of daily intake.16 On the contrary, whey protein-derived dipeptide, IW, increased renin mRNA expression in the kidney.27 This discrepancy could be due to the difference in peptide structure and SHR tissues, in addition to other unknown factors.