Evaluation of dimethyl sulphoxide effects on initial response to endotoxin in the horse.
BACKGROUND
Endotoxaemia is one of the most severe and ubiquitous disease processes in horses. Although dimethyl sulphoxide (DMSO) is used clinically in horses, there is no study indicating its efficacy in endotoxaemic horses.


OBJECTIVE
DMSO ameliorates the clinical response to i.v. lipopolysaccharide (LPS) administration.


METHODS
Eighteen horses were assigned randomly to one of 4 groups: Normosol-LPS (0.2 mug/kg bwt, i.v.); DMSO (1 g/kg bwt, i.v.)-saline; high-dose DMSO (1 g/kg bwt, i.v.)LPS; low-dose DMSO (20 mg/kg bwt, i.v.)-LPS. Horses participating in the DMSO-saline group were later assigned randomly to one of the LPS groups. Data for physical parameters, white blood cell counts, plasma TNF-alpha, and blood lactate and glucose concentrations were examined for the effect of treatment using a repeated-measures mixed-model ANOVA. A value of P<0.05 was considered significant.


RESULTS
Endotoxaemia occurred in all horses receiving LPS, as indicated by the clinical score, physical parameters, haemoconcentration and leucopenia. High-dose DMSO ameliorated the effect of LPS on fever. DMSO, at either dose, but did not have a significant effect on LPS-induced changes in all other evaluated parameters.


CONCLUSIONS
In this study, DMSO had minimal effects on clinical signs of induced endotoxaemia in horses. The effects were manifested by amelioration of LPS-induced fever.
Kelmer
G
G
Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Tennessee, 2407 River Drive, Knoxville, TN 37996, USA.
Doherty
T J
TJ
Elliott
S
S
Saxton
A
A
Fry
M M
MM
Andrews
F M
FM
D000704:Analysis of Variance; D000818:Animals; D019540:Area Under Curve; D001831:Body Temperature / Q000187:drug effects; D004121:Dimethyl Sulfoxide / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D019446:Endotoxemia / Q000139:chemically induced / Q000188:drug therapy / Q000662:veterinary*; D004731:Endotoxins / Q000494:pharmacology; D005260:Female; D005334:Fever / Q000188:drug therapy / Q000662:veterinary*; D006339:Heart Rate / Q000187:drug effects / Q000502:physiology; D006734:Horse Diseases / Q000139:chemically induced / Q000188:drug therapy*; D006736:Horses; D008070:Lipopolysaccharides / Q000494:pharmacology; D008297:Male; D011897:Random Allocation; D012720:Severity of Illness Index; D013997:Time Factors; D016896:Treatment Outcome
D004731:Endotoxins; D008070:Lipopolysaccharides; D004121:Dimethyl Sulfoxide