Homozygotes: A targeting vector was designed to insert a neomycin resistance (neo) cassette into exon 2 of the solute carrier family 9 (sodium/hydrogen exchanger), member 4 (Slc9a4 or Nhe4) gene, abolishing gene function. Homozygous Nhe4-/- mice are viable, fertile, and normal in size. Nhe4 is expressed on the basolateral membrane of gastric parietal cells and zymogenic (chief) cells, and is required for normal levels of gastric acid secretion, secretory membrane development, and parietal cell and chief cell differentiation. These mutant mice display a reduction in gastric acid and their gastric mucosa contain reduced numbers of parietal cells, a loss of mature chief cells, increased numbers of mucous and undifferentiated cells, and an increase in the number of necrotic and apoptotic cells. In addition, the parietal cells of Nhe4-/- mice exhibit limited development of canalicular membranes and a virtual absence of tubulovesicles. These mice may be useful for studying gastric acid secretion, gastric epithelial cell differentiation, and development of secretory canalicular and tubulovesicular membranes.
Heterozygote: Heterozygous mice are viable, fertile, and normal in size. They exhibit normal growth and are phenotypically similar to wildtype mice.

These Slc9a4 (or Nhe4) knockout mice exhibit a reduction in gastric acid, reduced numbers of parietal cells, a loss of mature chief cells, increased numbers of mucous and undifferentiated cells, and an increase in the number of necrotic and apoptotic cells. These mice may be useful for studying gastric acid secretion, gastric epithelial cell differentiation, and development of secretory canalicular and tubulovesicular membranes.

This strain is hosted by NIH's MMRRC, which partners with JAX for the distribution of this and other strains. For additional information and to purchase, please visit the MMRRC site.