Interleukin 1 alpha and an interleukin 1 beta fragment are somnogenic
Obal, F.; Opp, M.; Cady, A.B.; Johannsen, L.; Postlethwaite, A.E.; Poppleton, H.M.; Seyer, J.M.; Krueger, J.M.
American Journal of Physiology 259(3 Pt 2): R439-R446
1990
ISSN/ISBN: 0002-9513 PMID: 2396703 Document Number: 360866
The somnogenic activity of interleukin 1.beta. (IL-1.beta.) has previously been established. Interleukin 1.alpha. (IL-1.alpha.) is a distinct gene product that possesses similar biological activities. We report here that IL-1.alpha., like IL-1.beta., has the capacity in rabbits to enhance non-rapid-eye-movement sleep, electroencephalographic slow-wave (0.5-3.5 Hz) voltages, and body temperatures and to inhibit rapid-eye-movement sleep. After IL-1.alpha., sleep remained episodic, and at the doses used no abnormal behavior was observed. Several synthetic IL-1.alpha. and IL-1.beta. peptides were also tested in vivo for somnogenic and pyrogenic activity and in vitro for their ability to stimulate prostaglandin E2 (PGE2) production by fibroblasts and proliferation of T-cells. Only IL-1.beta.-(208-240) enhanced non-rapid-eye-movement sleep and body temperature, although both IL-1.beta.-(208-240) and IL-1.alpha.-(223-250) stimulated PGE2 production; both of these peptides failed to stimulate T-cell production. In contrast, four other IL-1 peptides were nonpyrogenic and somnogenically inactive yet stimulated T-cell proliferation. We conclude that the components of IL-1 required for sleep and temperature activities are different from those required for T-cell proliferation.