Expression of Jejunal Apical Excitatory Amino Acid Carrier 1 (EAAC1) is Maintained in Piglets with Bowel Inflammation

Abstract

The objective of this study was to examine jejunal excitatory amino acid carrier 1 (EAAC1) expression in response to bowel inflammation induced with dextran sodium sulfate (DSS) in the piglet model. Piglets at the age of d 5 were fed a commercial source of liquid formula, fitted with an intra‐gastric catheter and administrated with either 2.5 g of DSS/kg body weight (DSS, n = 5) in saline or saline (control, n = 6) in two injections daily for a period of 10 d prior to jejunal tissue harvesting. Small and large bowel inflammations were confirmed with representative pro‐inflammatory cytokine profiling. Predominant EAAC1 immuno‐reactive bands of 57 and 73 kDa were detected in the jejunal homogenate and the apical membrane (AM), respectively, consistent with the nonglycosylated pre‐mature and the glycosylated mature forms of the EAAC1 protein. Expression of the 57‐kDa pre‐mature EAAC1 protein in the jejunal homogenate was lower (P < 0.05) in the DSS group compared with the control. However, there was no difference (P > 0.05) in abundance of the 73‐kDa mature EAAC1 in AM between the two groups. Furthermore, there was no difference (P > 0.05) in EAAC1 mRNA abundance between the DSS and the control groups. These results have suggested that expression of 73‐kDa mature EAAC1 protein in the gut apical membrane is maintained in piglets with during bowel inflammation. Supported by AMFNET of NSERC.