Towards the mechanism of protection against indomethacin induced gastro-intestinal ulceration by naloxone.

Activities of lysosomal hydrolases have been evaluated in relation to indomethacin and naloxone, using purified lysosomal fractions from rat intestinal mucosa. Indomethacin treatment significantly decreased (p less than 0.001) lysosomal enzyme activities in purified lysosomes, while an increase in the activities was observed in intestinal homogenates. However, indomethacin could not affect lysosomal system in animals pretreated with naloxone, thereby establishing that naloxone neutralises the effect of indomethacin.