Molecular cloning, tissue distribution and ontogenetic expression of sodium proton exchanger isoform 2 (NHE-2) mRNA in the small intestine of pigs.

摘要

Molecular cloning, tissue distribution and ontogenetic regulation of sodium/proton exchanger isoform 2 (NHE-2) mRNA expression were evaluated in the pig small intestine during postnatal development. The 2872-bp porcine full cDNA sequence of the NHE-2 (EF672046) cloned in this study showed 80% and 70% homology with known human and mouse gene sequence, respectively. Hydrophobic prediction suggests 13 putative membrane-spanning domains within porcine NHE-2. The porcine NHE-2 mRNA was detected in the brain, liver, kidney, heart, lung, small intestine and muscle. The small intestine had the highest NHE-2 mRNA abundance and the brain, lung and liver had the lowest NHE-2 mRNA abundance (P<0.05). Along the longitudinal axis, the duodenum had the highest NHE-2 mRNA abundance and the ileum and colon had the lowest NHE-2 mRNA abundance (P<0.05). The NHE-2 mRNA level was increased from day 1 to day 26 in the duodenum (P<0.05) and dropped dramatically on day 30 (P<0.05). There is no difference between day 1 and day 7 (P