In Vivo and In Vitro Expression of Porcine Zinc Transporter (Znt) 1 mRNA

Zinc transporter (ZnT1) mRNA is differentially expressed in vivo, in weaned pig tissues, and in vitro, in response to additions of zinc sulphate or antibiotics. Summary Preliminary experiments were carried out to evaluate in vivo expression of zinc transporter (ZnT) 1 mRNA in a panel of tissues obtained from weaned pigs and to evaluate in vitro changes in ZnT1 mRNA in a porcine jejunal epithe-lial cell line (IPEC-J2) treated with low (40 µM) or high (80 µM) concentrations of zinc sulphate (ZnSO 4) or, in a separate experiment, with low (50 µg/ml) or high (100 µg/mL) concentrations of antibiotics (as gentamicin; GENT). Lipopolysac-charide (LPS; 10 ng/mL) was included as a negative control in both experiments. Zinc transporter 1 mRNA was detected in all tissues evaluated with the greatest level of expression observed in the tonsil. A treatment × time interaction was not observed for IPEC-J2 cells treated with ZnSO 4 ; however, the addition of high ZnSO 4 tended (P = 0.08) to increase ZnT1 mRNA expression when means were averaged among all time points. Exposure of IPEC-J2 cells to GENT resulted in a signifi cant treatment × time interaction (P < 0.005) with increases in ZnT1 mRNA observed at 3 (low GENT) and 6 (low and high GENT) hours post-treatment compared to CTL-or LPS-treated cells. This research indicates that ZnT1 mRNA is differentially expressed in vivo, in a panel of porcine tissues, and in vitro, in IPEC-J2 cells exposed to low or high concentrations of zinc or antibiotics.