Effects of alcohol on laminin in rat gastric mucosa.

Following ethanol exposure, the gastric surface epithelium often exfoliates, leaving a denuded basal lamina. Viable cells from the gland migrate along the basal lamina to repair the defect, a process known as restitution. Laminin, the major non-collagenous glycoprotein of basal laminae, functions in cellular adhesion and migration and, therefore, any alteration of this molecule by ethanol may influence subsequent restitution. After a 5 or 60 minutes treatment with saline, 50% or 100% ethanol, gastric tissues were removed from fasted female Sprague-Dawley rats, fixed in 1% paraformaldehyde and processed in Lowicryl. Once embedded and sectioned, specimens were incubated in anti-laminin followed by protein A-gold. The area of lamina densa from interfoveolar, pit and gland regions was measured and gold particles counted. Absolute ethanol caused diminished immunogold binding in all regions at all time periods, except the gland at 60 minutes. Exposure to 50% ethanol for 5 minutes did not alter laminin binding, although 60 minutes after 50% alcohol, laminin immunolabelling was increased. Alcohol concentration alters laminin immunogold binding, and therefore may influence restitution.