Interleukin-1[beta] enhances spinal cord blood flow after
intrathecal administration in the normal rat.
Plata-Salam[acute]an, Carlos R., Gina Kelly, Cynthia Agresta, Karen
Taylor, and Steven K. Salzman.
Alfred I. duPont Institute, P.O. Box 269, Wilmington, Delaware
19899, and School of Life and Health Sciences, University of
Delaware, Newark, Delaware 19716
APStracts 2:0153R, 1995.
The effects of acute intrathecal (i.t.) recombinant human interleukin
-1[beta] (rhIL-1[beta]) administration on spinal cord blood flow
(SCBF), volume (SCBVo) and velocity (SCBVe) were determined by laser
-doppler flowmetry in normal anesthetized rats using a randomized and
blinded protocol. The i.t. administration of rhIL-1[beta] (0.16 to 16
ng) produced a dose-dependent increase in SCBF that was not related
to changes in blood pressure, arterial pH/pO2/pCO2, or spinal cord
temperature. The IL-1[beta]-induced enhancement of SCBF was directly
proportional to the resultant elevation of spinal cord rhIL-1[beta]
content, and was significantly correlated with an elevated blood
velocity. The IL-1 receptor antagonist (IL-1ra, in concentrations 50-
and 200-fold higher than IL-1[beta]) completely blocked the IL
-1[beta]-induced increase in SCBF when both compounds were
administered concomitantly, but when administered alone, IL-1ra did
not affect SCBF or other parameters. This suggests that IL-1[beta]
action was mediated by a specific interaction with an IL-1 membrane
receptor site. The results suggest a role of IL-1[beta] in the
regulation of spinal cord hemodynamics. A potential pharmacological
approach using IL-1 agonists for the treatment of the delayed
appearance of post-traumatic spinal ischemia is proposed.
Received 28 December 1994; accepted in final form 30 May 1995.
APS Manuscript Number R737-4.
Article publication pending Am. J. Physiol. (Regulatory Integrative
Comp. Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 6 July 1995.