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21.
López Ordieres MG Álvarez-Juliá A Kemmling A Rodríguez de Lores Arnaiz G 《Neurochemical research》2011,36(12):2278-2286
We have previously showed that peptide neurotensin inhibits neuronal Na+, K+-ATPase activity, an effect which involves high affinity neurotensin receptor. Nitric oxide (NO) acts as a neurotransmitter
or as a neuromodulator when it is synthesized by neuronal nitric oxide synthase. Neurotensin effect on Na+, K+-ATPase activity was evaluated in cortical synaptosomal membranes isolated from rats injected at 3, 4 and 5 postnatal days
with saline (control) or N (ω)-nitro-l-arginine methyl esther (L-NAME), a nitric oxide synthase inhibitor. Assays were carried out at two stages: juvenile (35 days)
and adult (56 days) ages. In an open field task, results recorded in juvenile rats markedly differed from those obtained in adult rats. The presence
of neurotensin at 3.5 × 10−8–3.5 × 10−6 M concentration decreased 16–34% Na+, K+-ATPase activity in membranes purified from control animals. At variance, the peptide failed to alter this enzyme activity
in membranes obtained after L-NAME treatment. After administration of L-NAME, [3H]-ouabain binding to membranes isolated from adult male rats decreased 64% in the presence of 1.0 × 10−6 M neurotensin, a peptide concentration which only slightly decreased binding to membranes isolated from juvenile rats. It
is postulated that early postnatal NO dysfunction may exert a permanent change in neurotensin system that influence later
Na+, K+-ATPase response to neurotensin. 相似文献
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Ricardo Guerra Peixe Marcela Santana Bastos Boechat Alba Lucinia Peixoto Rangel Rh?nia Fran?a Gomes Rosa Maria Luiza Petzl-Erler Lilian MG Bahia-Oliveira 《Memórias do Instituto Oswaldo Cruz》2014,109(1):99-107
The association of single nucleotide polymorphisms (SNPs) in the interferon (IFN)-γ
gene ( IFNG ) with different types of retinal scar lesions
presumably caused by toxoplasmosis were investigated in a cross-sectional
population-based genetic study. Ten SNPs were investigated and after Bonferroni
correction, only the associations between SNPs rs2069718 and
rs3181035 with retinal/retinochoroidal scar lesions type A (most
severe scar lesions) and C (least severe scar lesions), respectively, remained
significant. The associations of two different IFNG SNPs with two
different types of retinal lesions attributable to toxoplasmosis support the
hypothesis that different inflammatory mechanisms underlie the development of these
lesions. The in vitro analysis of IFN-γ secretion by peripheral blood mononuclear
cells stimulated with Toxoplasma gondii antigens was also
investigated. The association between SNP rs2069718 and type A scar
lesions revealed that differential IFN-γ levels are correlated with distinct
genotypes. However, no correlation was observed with IFN-γ secretion levels and the
SNP rs3181035 , which was significantly associated with type C scar
lesions. Our findings strongly suggest that immunogenetic studies of individuals with
congenital or postnatally acquired infection are needed to better understand the role
of IFN-γ and its polymorphisms in the pathogenesis of ocular toxoplasmosis. 相似文献
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Tiana Baqueiro Momtchilo Russo Virgínia MG Silva Thayna Meirelles Pablo RS Oliveira Eliane Gomes Renato Barboza Ana T Cerqueira-Lima Camila A Figueiredo Lain Pontes-de-Carvalho Neuza M Alcantara-Neves 《Respiratory research》2010,11(1):51
Background
The dust mite Blomia tropicalis is an important source of aeroallergens in tropical areas. Although a mouse model for B. tropicalis extract (BtE)-induced asthma has been described, no study comparing different mouse strains in this asthma model has been reported. The relevance and reproducibility of experimental animal models of allergy depends on the genetic background of the animal, the molecular composition of the allergen and the experimental protocol.Objectives
This work had two objectives. The first was to study the anti-B. tropicalis allergic responses in different mouse strains using a short-term model of respiratory allergy to BtE. This study included the comparison of the allergic responses elicited by BtE with those elicited by ovalbumin in mice of the strain that responded better to BtE sensitization. The second objective was to investigate whether the best responder mouse strain could be used in an experimental model of allergy employing relatively low BtE doses.Methods
Groups of mice of four different syngeneic strains were sensitized subcutaneously with 100 μg of BtE on days 0 and 7 and challenged four times intranasally, at days 8, 10, 12, and 14, with 10 μg of BtE. A/J mice, that were the best responders to BtE sensitization, were used to compare the B. tropicalis-specific asthma experimental model with the conventional experimental model of ovalbumin (OVA)-specific asthma. A/J mice were also sensitized with a lower dose of BtE.Results
Mice of all strains had lung inflammatory-cell infiltration and increased levels of anti-BtE IgE antibodies, but these responses were significantly more intense in A/J mice than in CBA/J, BALB/c or C57BL/6J mice. Immunization of A/J mice with BtE induced a more intense airway eosinophil influx, higher levels of total IgE, similar airway hyperreactivity to methacholine but less intense mucous production, and lower levels of specific IgE, IgG1 and IgG2 antibodies than sensitization with OVA. Finally, immunization with a relatively low BtE dose (10 μg per subcutaneous injection per mouse) was able to sensitize A/J mice, which were the best responders to high-dose BtE immunization, for the development of allergy-associated immune and lung inflammatory responses.Conclusions
The described short-term model of BtE-induced allergic lung disease is reproducible in different syngeneic mouse strains, and mice of the A/J strain was the most responsive to it. In addition, it was shown that OVA and BtE induce quantitatively different immune responses in A/J mice and that the experimental model can be set up with low amounts of BtE. 相似文献29.
A report on the meeting 'Rat Genomics and Models', Cold Spring Harbor, USA, 8-11 December 2005. 相似文献
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Previous work from this laboratory showed the ability of neurotensin to inhibit synaptosomal membrane Na(+), K(+)-ATPase activity, the effect being blocked by SR 48692, a non-peptidic antagonist for high affinity neurotensin receptor (NTS1) [López Ordieres and Rodríguez de Lores Arnaiz 2000; 2001]. To further study neurotensin interaction with Na(+), K(+)-ATPase, peptide effect on high affinity [(3)H]-ouabain binding was studied in cerebral cortex membranes. It was observed that neurotensin modified binding in a dose-dependent manner, leading to 80% decrease with 1 × 10(-4)M concentration. On the other hand, the single addition of 1 × 10(-6)M, 1 × 10(-5)M and 1 × 10(-4)M SR 48692 (Sanofi-Aventis, U.S., Inc.) decreased [(3)H]-ouabain binding (in %) to 87 ± 16; 74 ± 16 and 34 ± 17, respectively. Simultaneous addition of neurotensin and SR 48692 led to additive or synergic effects. Partial NTS2 agonist levocabastine inhibited [(3)H]-ouabain binding likewise. Saturation assays followed by Scatchard analyses showed that neurotensin increased K(d) value whereas failed to modify B(max) value, indicating a competitive type interaction of the peptide at Na(+), K(+)-ATPase ouabain site. At variance, SR 48692 decreased B(max) value whereas it did not modify K(d) value. [(3)H]-ouabain binding was also studied in cerebral cortex membranes obtained from rats injected i. p. 30 min earlier with 100 μg and 250 μg/kg SR 48692. It was observed that the 250 μg/kg SR 48692 dose led to 19% decrease in basal [(3)H]-ouabain binding. After SR 48692 treatments, addition of 1 × 10(-6)M led to additive or synergic effect. Results suggested that [(3)H]-ouabain binding inhibition by neurotensin hardly involves NTS1 receptor. 相似文献