Effect of Ionizing Radiation on Prostaglandin‐like Activity in Tissues

Abstract

One to 7 days after whole body exposure of mice to a single dose of 700 R of x‐rays, little or no change was detected in prostaglandin‐like activity in the brain, blood and seminal vesicles. Slight increases in intestinal and renal tissue were not significant. In the lung, mean activity rose from 62 ng/g to a transient peak of 145 ng/g wet weight on the fourth day (P > 0.05). In the spleen, mean levels rose steadily from 13.2 ng/g to 259 ng/g on the fourth day (P < 0.01), and were still 184.4 ng/g on the seventh day. Prostaglandin‐like activity was measured 4 days after single doses of 200–700 R. In the lung, a significant rise was produced by 600 and 700 R, and in the spleen by 200–700 R. Thin layer chromatography showed that part of the prostaglandin‐like activity in spleen extracts had an RF similar to that of [3H]‐prostaglandin E1, and part to that of [3H]‐prostaglandin F2α. Splenic tissue from mice exposed to 700 R four days earlier, inactivated prostaglandin E1 less potently than did tissue from non‐irradiated mice.

Prostaglandin-like material extracted from squamous carcinomas of the head and neck

“…Necrosis, inflammation and related changes are likely to be more pronounced after irradiation and chemotherapy, and total amounts of prostaglandins were often higher in tumours removed within 3 months of such treatment. Various forms of local damage, including ionizing radiation (Eisen & Walker, 1976) can increase the amounts of prostaglandin in tissue.…”

Plasma prostaglandins in mucositis due to radiotherapy and chemotherapy for head and neck cancer

“…The side effect of diarrhoea following pelvic irradiation is relieved by aspirin, and so probably involves prostaglandins (Mennie et al, 1975). Radiation can increase the amount of prostaglandin-like material extracted from tissues (Eisen & Walker, 1976. Furthermore, some chemotherapeutic drugs can release prostaglandins from cells (Levine, 1977).…”

“…In a pilot study, we have examined the part played by prostaglandins, since these contribute to the signs and symptoms of acute inflammation (Vane, 1974). Elevated amounts of prostaglandins or their metabolites seem to be present in the blood or excreted in the urine in some cancer patients (see Bennett, 1979) and the amounts of prostaglandin-like material extracted from otherwise normal tissue in animal experiments can be increased by irradiation (Eisen & Walker, 1976 or chemotherapeutic drugs (Levine, 1977). In the opossum, radiation caused oesophagitis which was inhibited by the prostaglandin-synthesis inhibitor indomethacin and worsened by treatment with a stable analogue of prostaglandin E2 (Northway et al, 1980).…”

Effect of exposure to radiation on the inflammatory process and its influence by diclofenac

“…In addition, there is evidence to suggest that ionizing radiation affects prostaglandin levels in animal tissues (Eisen & Walker, 1976;Trocha & Catravas, 1980). Thus, prostaglandin levels have been found to increase within several hours after exposure of mice to X-rays and to remain elevated for several days, especially in radiosensitive tissues such as the spleen and thymus (Eisen & Walker, 1976). Both prostaglandins and lysosomal enzymes are known mediators of cellular injury and inflammation.…”

“…The increase in the activity of lysosomal hydrolases and proteinases to abnormally high levels in many mammalian tissues after radiation exposure was said to be related to an increase in cyclic nucleotide synthesis (Trocha & Catravas, 1980). In addition, there is evidence to suggest that ionizing radiation affects prostaglandin levels in animal tissues (Eisen & Walker, 1976;Trocha & Catravas, 1980). Thus, prostaglandin levels have been found to increase within several hours after exposure of mice to X-rays and to remain elevated for several days, especially in radiosensitive tissues such as the spleen and thymus (Eisen & Walker, 1976).…”