Implication of Prostaglandins and Histamine H1 and H2 Receptors in Radiation-Induced Temperature Responses of Rats
Abstract
Exposure of rats to 1-15 Gy gamma radiation cobalt 60 induced hyperthermia, whereas 20-200 Gy induced hypothermia. Exposure either to the head or to the whole body to 10 Gy induced hyperthermia, while body-only exposure produced hypothermia. This observation indicates that radiation-induced fever is a result of a direct effect on the brain. The hyperthermia due to 10 Gy was significantly attenuated by the pre- or post-treatment with a cyclooxgenase inhibitor, indomethacin. Hyperthermia was also altered by the central administration of a mu receptor antagonist naloxone but only at low doses of radiation. These findings suggest that radiation-induced hyperthermia may be mediation through the synthesis and release of prostaglandins in the brain and to a lesser extent to the release of endogenous opioid peptides. The release of histamine acting on H(1) and H(2) receptors may be involved in radiation-induced hypothermia since both the H(1) receptor antagonist, mepyramine, and H(2) receptor antagonist, cimetidine, antagonized the hypothermia. The results of these studies suggested that the release of neurohumoral substances induced by exposure to ionizing radiation is dose dependent and has different consequences on physiological processes such as the regulation of body temperature. Furthermore, the antagonism of radiation-induced hyperthermia by indomethacin may have potential therapeutic implications in the treatment of fever resulting from accidental irradiations. Reprints.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1988
- Accession Number
- ADA203280
Entities
People
- G. A. Mickley
- Sathasiva B. Kandasamy
- Walter A. Hunt
Organizations
- Armed Forces Radiobiology Research Institute