Effect of nitric oxide metabolism upon peripheral blood chemiluminiscence and leukocyte and erythrocyte adherence in multiple sclerosis.
BACKGROUND
It has become increasingly apparent that nitric oxide (NO) and related metabolic and effector systems play an important role in immune regulations, in inflammatory response and in cellular and tissue damage in multiple sclerosis (MS) and in its experimental models.


OBJECTIVE
Various adherence interactions and metabolism of reactive oxygen species belong to the cellular functions associated with NO metabolism. The aim of the present study was to evaluate the effect of chemical compounds affecting NO metabolism on adhesive properties of leukocytes and erythrocytes and on the blood chemiluminiscence in MS patients in comparison with controls. The effects of NG-Methyl-L-Arginine (NGMLA), a specific competitive NO antagonist, L-arginin, NO precursor, and sodium nitroprusside, an NO-releasing agent were tested.


METHODS
Luminol dependent chemiluminiscence was measured with and without respective drug administration, the results were expressed as chemiluminiscence index. Adherence of peripheral blood cells to nylon wool was used for the adherence studies, the results were expressed in a form of adhesivity index. Studies were performed in a group of patients with active multiple sclerosis, in a group of neurological controls and in a group of healthy controls. The differences between MS patients and control groups were statistically evaluated using Mann and Whitney U-test.


RESULTS
Sodium nitroprusside stimulated the luminol-dependent chemiluminiscence in MS patients and inhibited it in both control groups. The difference between MS patients and the control patient subgroup was proved to be statistically significant. Statistically significant inhibition of leukocyte adherence by arginine was found in MS patients in comparison to healthy controls, in whom stimulation of adherence was observed. When differentiating the effect of the agents upon particular leukocyte subpopulations the only statistically significant difference was found with arginine and granulocytes, the trend being similar as in the total leukocyte adherence. Sodium nitroprusside further stimulated the adherence of erythrocytes in MS patients and inhibited it in controls.


CONCLUSIONS
Results indicate nitric oxide-dependent alterations of oxidative metabolic burst and of cellular adherence properties in patients with active multiple sclerosis. Our findings also question possible participation of granulocytes and erythrocytes in multiple sclerosis pathogenetic cascade.
Mayer
M
M
Department of Rehabilitation, Faculty Hospital, Olomouc, Czech Republic. michal@tunw.upol.cz
Hermanova
Z
Z
D000328:Adult; D002448:Cell Adhesion; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004912:Erythrocytes / Q000502:physiology*; D005260:Female; D006801:Humans; D007962:Leukocytes / Q000502:physiology*; D008163:Luminescent Measurements; D008165:Luminol / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000097:blood / Q000378:metabolism*; D009569:Nitric Oxide / Q000502:physiology*; D019001:Nitric Oxide Synthase / Q000494:pharmacology; D009599:Nitroprusside / Q000494:pharmacology; D019323:omega-N-Methylarginine / Q000494:pharmacology
D004791:Enzyme Inhibitors; D009599:Nitroprusside; D019323:omega-N-Methylarginine; D009569:Nitric Oxide; D008165:Luminol; D019001:Nitric Oxide Synthase