Fibroblast growth factor (fgf) but not basic fgf induces sleep and
fever in rabbits..
Knefati, Mohamed, Christopher Somogyi, Levente Kap[acute]as, Todd Bourcier,
and James M. Krueger.
Department of Neurology and Baptist Memorial Hospital Sleep
Disorders Center and Physiology and Biophysics, University of
Tennessee, Memphis, TN 38163 USA
APStracts 2:0040R, 1995.
Acidic fibroblast growth factor (FGF) and basic FGF belong to a growth
factor family; interleukin-1, another member of that family, is
involved in sleep regulation. FGFs and interleukin-1 share structural
and functional features: we determined, therefore, whether acidic FGF
and basic FGF were somnogenic. Male New Zealand White rabbits were
provided with electroencephalograph (EEG) electrodes, a brain
thermistor, and a lateral intracerebroventricular (i.c.v.) cannula.
The animals were injected i.c.v. with isotonic NaCl (control) and on
separate days with one of three doses of acidic or basic FGF (0.01,
0.1, 1.0 mg) or with heat-treated acidic FGF (1.0 mg). The EEG, brain
temperature, and motor activity were recorded for 23 hours. The
biological activity of basic FGF was determined in vitro by its
ability to induce DNA synthesis in rat aortic smooth muscle cells.
Acidic FGF induced prolonged dose-related increases in non-rapid eye
movement sleep beginning in the first postinjection hour and
continuing for 12-23 hours after the treatment. Acidic FGF also
induced fevers of about 1 degrees C after the 1.0 mg dose. Both activities of
acidic FGF were lost after heat-treatment. In contrast, basic FGF
lacked somnogenic and pyrogenic activity, though it did induce DNA
synthesis. Current results suggest that acidic FGF is part of the
complex cytokine network in brain involved in sleep regulation.
Received 12 September 1994; accepted in final form 22 January
1995.
APS Manuscript Number R509-4.
Article publication pending Am. J. Physiol. (Regulatory Integrative
Comp. Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 25 February 1995.