Fig. 4.

Real-time PCR and Western blot for acetyl-CoA:1-O-alkyl-sn-glycero-3-phosphocholine acetyltransferase (lyso-PAF AT), the enzyme responsible for production of platelet-activating factor. HET-1A cells were treated with the selected HCl exposure protocol and then used to determine lyso-PAF AT mRNA expression by real-time PCR (left) and protein expression (middle) by Western blotting. Relative mRNA expression was calculated with respect to mRNA from untreated cells. Repeated exposures to pH 5 over 48 h caused a significant increase in mRNA and protein expression for lyso-PAF AT (*P < 0.01). Western blot results are shown as relative optical density normalized to GAPDH. Values are means ± SE; n = 3 for 3 different sets of data from 3 separate experiments. Right: real-time PCR for human biopsies from patients with erosive esophagitis (EE) and normal controls. Increased lyso-PAF AT mRNA in EE patients parallels increase in HET-1A cells after exposure to HCl.