Possible involvement of prostaglandins in increases in rat plasma adrenocorticotropic hormone and corticosterone levels induced by radiation and interleukin-1 alpha alone or combined.

Exposing rats to 1-10 Gy of ionizing radiation increased plasma adrenocorticotropic hormone (ACTH) and corticosterone (CORT) levels. In both irradiated and nonirradiated rats, recombinant human interleukin-1 alpha (rhIL-1 alpha; 1 hr before radiation/sham exposure) enhanced plasma ACTH and CORT levels. Indomethacin, a cyclooxygenase inhibitor, attenuated plasma ACTH and CORT levels induced by radiation. Indomethacin also attenuated ACTH and CORT levels induced by radiation and interleukin-1 alpha alone or combined. These results suggest that prostaglandins are involved in the increase in plasma ACTH and CORT levels induced by radiation and rhIL-1 alpha alone or combined.