Ultrasonically nebulized distilled water prevents exogenous histamine hyperreactivity in Toxocara canis-infected mice.
OBJECTIVE
This study examines the effect of ultrasonically nebulized distilled water inhalation on the systemic histamine hyperreactivity of Toxocara canis-infected mice.


METHODS
Uninfected and T. canis-infected mice received an intravenous sublethal dose of histamine and lethality rates were documented. At 24 days post infection, infected mice received ultrasonically nebulized distilled water inhalation for 1 h. Twenty-four hours later histamine levels were determined in bronchoalveolar lavage fluid as well as histamine lethality and toluidine blue-stained mast cell number in the lung.


RESULTS
T. canis-infected mice showed increased lethality after exposure to histamine in comparison to uninfected mice. Ultrasonically nebulized distilled water inhalation prevented histamine-induced lethality and reduced toluidine blue-stained mast cell numbers in the lung.


CONCLUSIONS
The correlation between decreases in stained mast cells in the lung after ultrasonically nebulized distilled water inhalation and inhibition of histamine-induced lethality in these animals suggests participation of mast cells in the phenomenon and could be helpful in understanding the mechanisms of hyperreactivity during helminth parasite infections.
Sá-Nunes
A
A
Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, 14040-903, São Paulo, Brazil.
Bolzoni
R M F
RM
Medeiros
A I
AI
Jamur
M C
MC
Oliver
C
C
Baruffi
M Dias
MD
Faccioli
L H
LH
D000707:Anaphylaxis / Q000139:chemically induced / Q000517:prevention & control; D000818:Animals; D005260:Female; D006632:Histamine / Q000008:administration & dosage* / Q000494:pharmacology*; D006967:Hypersensitivity / Q000150:complications / Q000517:prevention & control*; D007700:Kinetics; D008168:Lung / Q000187:drug effects / Q000469:parasitology / Q000473:pathology; D008407:Mast Cells / Q000166:cytology / Q000187:drug effects; D051379:Mice; D008807:Mice, Inbred BALB C; D009330:Nebulizers and Vaporizers; D012701:Serotonin / Q000494:pharmacology; D017166:Toxocara canis / Q000502:physiology*; D014120:Toxocariasis / Q000150:complications* / Q000469:parasitology; D014465:Ultrasonics; D014867:Water / Q000008:administration & dosage* / Q000737:chemistry
D014867:Water; D012701:Serotonin; D006632:Histamine