DMP-777-treated animals show marked foveolar hyperplasia in the fundus with the prominent expansion of diastase-resistant, PAS-positive surface mucous cells. DMP-777-treated rats display a marked reduction in H/K-ATPase staining parietal cells. DMP-777-induced loss of parietal cells is significantly ameliorated with coadministration of omeprazole. When DMP-777 is coadministered with omeprazole, there is an obvious decrease in BrdU-positive S-phase cells compared with rats that received DMP-777 alone [1]. After DMP-777(40 mg/kg; p.o.; monkeys) treatment, the only stereoisomer detected in the post-dose plasma samples is the starting material DMP-777, and no inversion of the configuration at positions 'a' and 'b' of DMP-777 has occurred in vivo [2]. Mist1-/- mice treated with DMP-777 show fewer chief cells to SPEM transitions and which treated with L635 demonstrates significantly fewer proliferative SPEM cells compared to control mice [3].