Effect of aging on gene expression rates of endothelin-1 and endothelin-2/vasoactive intestinal contractor in ethanol-induced gastric mucosal injury of the mouse

To elucidate the physiological roles of endothelin-1 (ET-1) and endothelin-2 (ET-2)/vasoactive intestinal contractor (VIC) in gastric injury of mice, we measured the gene expression rates of ET-1 and ET-2/VIC in gastric injury induced by ethanol in young (8 weeks) and old (>33 weeks) mice. Mice that were fasted for 24h were injected with absolute ethanol intragastrically and killed after 1 or 4h of ethanol exposure. The size of the gastric lesions increased gradually after ethanol exposure and was at its greatest after 4 h, in both young and old mice. The gene expression of ET-1 tended to increase after 1h and to decrease by 4h of ethanol exposure in both young and old mice. However, the gene expression of ET-2/VIC in young mice increased significantly after 1 and 4h of ethanol exposure, whereas the gene expression of ET-2/VIC in the old mice did not change after ethanol exposure. Based on these results, we conclude that aging influences the gene expression of ET-2/VIC but not lesion size or gene expression of ET-1 in ethanol-induced gastric injury in the mouse. We therefore suggest that regulation of gene expression of these two genes differs during the course of aging.