 Lactate dehydrogenase(LDH) is one such enzyme that directly competes with GRHPR for substrates and converts glyoxylate to oxalate.However, due to the relatively large concentration of NADPH compared to NADH under normal cellular concentration, the GRHPR activity is greater than that of LDH so the production of glycolate is dominant.Primary hyperoxaluria is a condition that results in the overproduction of oxalate which combines with calcium to generate calcium oxalate, the main component of kidney stones.