RESUMO
To explore the chemopreventive effects of meloxicam, grapefruit juice or the combination against the induction of colonic aberrant crypt foci in the rat model. Male albino rats were divided into 5 groups. In group A [positive control], rats received oral dimethylhydrazine, which in Group B, rats received oral meloxicam and dimethlhydrazine. Regarding group C, rats were allowed to drink grapefruit juice, ad.libitum, then received dimethlhydrazine, and in group D, rats received the combination [meloxicam and grapefruit juice]. Group E [negative control], received oral saline only. Blood samples were collected every week from group B and D for meloxicam analysis. All animals were sacrificed under ether anesthesia on the last day of the 15th weeks. Colon tissues were removed, cut open longitudinally, rinsed with saline and stained with 0.25% methylene blue and then examined microscopically for the presence of aberrant crypt follicle. Samples containing aberrant crypt foci were sectioned at 4 micro m thickness and stained with hematoxyline and eosin. Aberrant Crypt Foci [ACF] are considered as an early neoplastic cell lesions that are characterized by unstable colonic epithelia which encompasses many dysplastic crypts. The data obtained in this study revealed that rats which received meloxicam or the combination [meloxicam and grapefruit juice] resulted in a significant reduction in the incidence of aberrant crypt foci counts compared to the control group. While, rats allowed to only drink grapefruit juice, showed insignificant reduciotn of aberrant crypt foci count. Furthermore, a significant increase in plasma level of meloxicam was detected in rats that received the combination. It is concluded that the addition of grapefruit juice to meloxicam in the treatment resulted in a greater chemopreventive activity than meloxicam or grapefruit juice. Furthermore, grapefruit juice resulted in a significant rise of plasma level of meloxicam. This is the first time to report the interaction between meloxicam and grapefruit