Similarities and differences in the cytoprotection induced by PGI2 and beta-carotene in experimental ulcer

It was earlier known that PGI2 and beta-carotene have a cytoprotective effect, but the similarities and the differences of their mechanisms were not clear. The gastric mucosal lesions were produced by ig. administration of 1 ml 96% ethanol and 1 ml 0.6 N HCl in rats. The 5 and 50 micrograms/kg dose of PGI2 and the 1 and 10 mg dose of beta-carotene was given 30 min. earlier. The animals were sacrified 1, 5, 15, 30 and 60 minutes after the administration of the necrotizing agent. The number and the severity of gastric mucosal lesions were noted. It was found that the number and the severity of gastric ulcers were dose-dependently decreased in each model after using either PGI2 or beta-carotene. The inhibiting effect of PGI2 appeared in the first last 15 minutes while beta-carotene was effective from 15 to 60 minutes.

The mechanism of the cytoprotection induced by PGI2 differ from the beta-carotene induced one. PGI2 plays a part in the earlier vascular phase. beta-carotene modulates the repair mechanisms.