Leishmaniasis is a parasitic disease that leads to chronic inflammation. Macrophages, depending on their activation state, are either hosts or killers of the parasites. Downregulation of nitric oxide (NO) synthesis by the parasite infecting the macrophages has been proposed to be an important evading mechanism based on in vitro studies. We confirmed inhibition of NO release by macrophages infected with Leishmania amazonensis in vitro. To examine the role of the parasite in regulating NO production in vivo, we monitored systemic NO levels elicited by challenging naive and L. amazonensis-infected BALB/c mice with lipopolysaccharide (LPS). Animals were challenged after 1, 2, 6, and 9 wk of infection. NO production was monitored by electron paramagnetic resonance spectroscopy as the levels of hemoglobin nitrosyl complexes (HbNO) present in the animal's blood. No significant differences in HbNO levels were observed between LPS-treated naive and inoculated mice at any time during infection. To control for increased macrophage numbers in infected mice, naive mice were injected with a macrophage cell line before LPS challenge; this treatment did not increase produced NO levels. The results argue against a major role for the parasite in downregulating NO production in vivo.
Skip Nav Destination
Article navigation
February 2000
PATHOLOGY|
February 01 2000
LEISHMANIA AMAZONENSIS INFECTION DOES NOT INHIBIT SYSTEMIC NITRIC OXIDE LEVELS ELICITED BY LIPOPOLYSACCHARIDE IN VIVO
Edlaine Linares;
Edlaine Linares
Departamento de Bioquimica, Instituto de Quimica, Universidade de São Paulo, CxP 26077, 05599–970, São Paulo, SP, Brazil
Search for other works by this author on:
Ohara Augusto;
Ohara Augusto
Departamento de Bioquimica, Instituto de Quimica, Universidade de São Paulo, CxP 26077, 05599–970, São Paulo, SP, Brazil
Search for other works by this author on:
Sandra Cristina Barão;
Sandra Cristina Barão
Departamento de Bioquimica, Instituto de Quimica, Universidade de São Paulo, CxP 26077, 05599–970, São Paulo, SP, Brazil
*Departamento de Parasitologia, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, CxP 6109, 13083–970, SP, Brazil.
Search for other works by this author on:
Selma Giorgio
Selma Giorgio
Departamento de Bioquimica, Instituto de Quimica, Universidade de São Paulo, CxP 26077, 05599–970, São Paulo, SP, Brazil
*Departamento de Parasitologia, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, CxP 6109, 13083–970, SP, Brazil.
†Corresponding author.
Search for other works by this author on:
J Parasitol (2000) 86 (1): 78–82.
Citation
Edlaine Linares, Ohara Augusto, Sandra Cristina Barão, Selma Giorgio; LEISHMANIA AMAZONENSIS INFECTION DOES NOT INHIBIT SYSTEMIC NITRIC OXIDE LEVELS ELICITED BY LIPOPOLYSACCHARIDE IN VIVO. J Parasitol 1 February 2000; 86 (1): 78–82. doi: https://doi.org/10.1645/0022-3395(2000)086[0078:LAIDNI]2.0.CO;2
Download citation file:
Sign in
Don't already have an account? Register
Client Account
You could not be signed in. Please check your email address / username and password and try again.
Could not validate captcha. Please try again.
Sign in via your Institution
Sign in via your InstitutionCiting articles via
SCOLICIDAL POTENCY OF BILE AGAINST ECHINOCOCCUS GRANULOSUS
İsa Caner Aydın, Noyan İlhan, Ahmet Şeker, Cem Batuhan Ofluoğlu, Fırat Mülküt, Nuri Emrah Göret, Kenan Çetin, Erdal Polat, Gökhan Aygün, Hasan Fehmi Kücük
SYNONYMIZATION OF PLACOBDELLA PICTA (VERRILL, ) (HIRUDINEA: GLOSSIPHONIIDAE) WITH DESCRIPTIONS OF TWO NEW SPECIES REVEALED BY MOLECULAR SPECIES DELIMITATION
Anna J. Phillips, Dennis J. Richardson, Charlotte I. Hammond, Brett C. Gonzalez, Eric A. Lazo-Wasem, William E. Moser
A RE-EVALUATION OF ZYGOCOTYLE (DIGENEA, PARAMPHISTOMOIDEA) BASED ON NEW GENETIC DATA SUPPORTS ITS SYNONYMIZATION WITH WARDIUS
Tyler J. Achatz, Dawn W. Cleveland, Sarah A. Orlofske, Robert C. Jadin, Jason Block, Lisa K. Belden, Hudson A. Pinto, Vasyl V. Tkach
DESCRIPTION OF A NEW SPECIES OF GYRINICOLA YAMAGUTI, 1938, FROM THE MONTEZUMA FROG, RANA MONTEZUMAE, IN THE TRANSITION ZONE BETWEEN THE NEARCTIC AND NEOTROPICS
Matthew A. Walker, Rogelio Aguilar-Aguilar, Virginia León-Règagnon, F. Agustín Jiménez
AN UPDATED KEY TO THE GENERA OF CALIGIDAE (COPEPODA: SIPHONOSTOMATOIDA)
James P. Bernot, Geoffrey A. Boxshall, Terue Cristina Kihara, Pedro Martínez Arbizu