The Journal of Neuroscience, December 15, 2000, 20(24):8980-8986
Nitric Oxide Modulation of Interleukin-1
-Evoked Intracellular
Ca2+ Release in Human Astrocytoma U-373 MG Cells and
Brain Striatal Slices
Antonella
Meini1,
Alberto
Benocci1,
Maria
Frosini1,
Gianpietro
Sgaragli1,
Gianpaolo
Pessina2,
Carlo
Aldinucci2,
Gisèle
Tchuisseu
Youmbi1, and
Mitri
Palmi1
1 Istituto di Scienze Farmacologiche and
2 Istituto di Fisiologia, Università di Siena, 53100 Siena, Italy
Intracellular Ca2+ mobilization and release into
mammal CSF plays a fundamental role in the etiogenesis of fever
induced by the proinflammatory cytokine interleukin-1
(IL-1
) and
other pyrogens. The source and mechanism of IL-1
-induced
intracellular Ca2+ mobilization was investigated
using two experimental models. IL-1
(10 ng/ml) treatment of rat
striatal slices preloaded with 45Ca2+
elicited a delayed (30 min) and sustained increase (125-150%) in
spontaneous 45Ca2+ release that was
potentiated by L-arginine (300 µM) and
counteracted by N-
-nitro-L-arginine
methyl ester (L-NAME) (1 and 3 mM). The nitric
oxide (NO) donors diethylamine/NO complex (sodium salt) (0.3 and
1 mM) and spermine/NO (0.1 and 0.3 mM) mimicked
the effect of IL-1
on Ca2+ release. IL-1
stimulated tissue cGMP concentration, and dibutyryl cGMP enhanced
Ca2+ release. The guanyl cyclase inhibitors
1H-[1,2,4]oxadiazole[4,3-a] quinoxalin-1-one (100 µM)
and 6-[phenylamino]-5,8 quinolinedione (50 µM)
counteracted Ca2+ release induced by 2.5 but not 10 ng/ml IL-1
. Ruthenium red (50 µM) and, to a lesser
extent, heparin (3 mg/ml) antagonized IL-1
-induced
Ca2+ release, and both compounds administered
together completely abolished this response. Similar results were
obtained in human astrocytoma cells in which IL-1
elicited a delayed
(30 min) increase in intracellular Ca2+
concentration ([Ca2+]i)
(402 ± 71.2% of baseline), which was abolished by 1 mM L-NAME. These data indicate that the
NO/cGMP-signaling pathway is part of the intracellular mechanism
transducing IL-1
-evoked Ca2+ mobilization in
glial and striatal cells and that the ryanodine and the
inositol-(1,4,5)-trisphosphate-sensitive Ca2+
stores are involved.
Key words:
interleukin-1
; nitric oxide; Ca2+
release; human astrocytoma cells; rat striatum; cGMP; Ca2+ stores; fever; neurotoxicity
Copyright © 2000 Society for Neuroscience 0270-6474/00/20248980-07$05.00/0