Kandasamy S B, Hunt W A
Behavioral Sciences Department, Armed Forces Radiobiology Research Institute, Bethesda, Maryland 20814-5145.
Radiat Res. 1990 Jan;121(1):84-90.
Exposure of rats to 1-15 Gy of gamma radiation induced hyperthermia, whereas exposure to 20-150 Gy produced hypothermia. Since radiation exposure induced the release of prostaglandins (PGs) and histamine, the role of PGs and histamine in radiation-induced temperature changes was examined. Radiation-induced hyper- and hypothermia were antagonized by pretreatment with indomethacin, a cyclooxygenase inhibitor. Intracerebroventricular administration of PGE2 and PGD2 induced hyper- and hypothermia, respectively. Administration of SC-19220, a specific PGE2 antagonist, attenuated PGE2- and radiation-induced hyperthermia, but it did not antagonize PGD2- or radiation-induced hypothermia. Consistent with an apparent role of histamine in hypothermia, administration of disodium cromoglycate (a mast cell stabilizer), mepyramine (H1-receptor antagonist), or cimetidine (H2-receptor antagonist) attenuated PGD2- and radiation-induced hypothermia. These results suggest that radiation-induced hyperthermia is mediated via PGE2 and that radiation-induced hypothermia is mediated by another PG, possibly PGD2, via histamine.
将大鼠暴露于1-15戈瑞的γ辐射会导致体温过高，而暴露于20-150戈瑞则会导致体温过低。由于辐射暴露会诱导前列腺素（PGs）和组胺的释放，因此研究了PGs和组胺在辐射诱导的体温变化中的作用。辐射诱导的体温过高和过低可通过用环氧化酶抑制剂吲哚美辛预处理来拮抗。脑室内注射PGE2和PGD2分别诱导体温过高和过低。给予特异性PGE2拮抗剂SC-19220可减弱PGE2和辐射诱导的体温过高，但不能拮抗PGD2或辐射诱导的体温过低。与组胺在体温过低中起明显作用一致，给予色甘酸钠（一种肥大细胞稳定剂）、美吡拉敏（H1受体拮抗剂）或西咪替丁（H2受体拮抗剂）可减弱PGD2和辐射诱导的体温过低。这些结果表明，辐射诱导的体温过高是通过PGE2介导的，而辐射诱导的体温过低是由另一种PG（可能是PGD2）通过组胺介导的。
