[Effect of radiotherapy on penetration of 5-FU in blood-pancreatic barrier in rats].

OBJECTIVE:To investigate the effect of radiotherapy dose on penetration of 5-FU (5-fluorouracil) in blood-pancreatic barrier in rats. METHODS:After the pancreatic region of the rats were irradiated by 2, 10, 20, 30 and 40 (Gy) doses of gamma-ray, we investigated the penetration ratio (PR) of 5-FU in the pancreatic tissue with HPLC assay. RESULTS:When treated with low-dose of gamma-ray (2 Gy), the PR of 5-FU increased obviously after 8 hours. But in the high-dose groups (>/= 10 Gy), the PR was less than or had no difference with control group. At the same time, we found that the islets had appeared pathological degeneration, while the pancreatic lobular structure, acini and ducts had no visible changes in 20 Gy group. CONCLUSIONS:After the treatment of low-dose of gamma-ray combined with 5-FU, the effect of chemoradiotherapy may be improved for enhanced PR of 5-FU in pancreatic tissue, and at the same time, chemotherapy and radiotherapy cooperate with each other. But in high dose groups (>/= 10 Gy), radiotherapy may reduce the effect of chemotherapy in acute phase. After high-dose radiotherapy, we should pay attention to the change of glucose-resistance of patient to reduce the incidence of radiotherapy complication.