ABSTRACT
The aim of this study was to develop and characterize a new model for evaluating nasal congestion in rats by using whole body plethysmography (WBP)-free moving application. Brown Norway rats were sensitized with 10% toluene-2, 4-diisocyanate (TDI) solution, and nasal congestion was provoked with 5% TDI. An increase in the enhanced pause (Penh) was recognized after being challenged with TDI. In addition, a significant increase in the Penh was observed following the intranasal application of histamine in TDI sensitized rats. Histamine H1 antagonists, such as chlorpheniramine and ketotifen suppressed the increase of Penh during the early-phase response. On the other hand, epinastine suppressed the increase of Penh in both the early and late phase responses. In conclusion, we developed an allergic rhinitis model that includes nasal congestion symptoms in Brown Norway rats, and this model may be useful for evaluating the effects of drugs on nasal congestion.
Subject(s)
Histamine H1 Antagonists/pharmacology , Nasal Mucosa/drug effects , Rhinitis/chemically induced , Toluene 2,4-Diisocyanate/pharmacology , Animals , Chlorpheniramine/pharmacology , Dibenzazepines/pharmacology , Disease Models, Animal , Histamine/pharmacology , Imidazoles/pharmacology , Ketotifen/pharmacology , Male , Nasal Mucosa/physiopathology , Plethysmography, Whole Body , Rats , Rats, Inbred BNABSTRACT
We examined the effect of propolis granular A. P. C on lung tumorigenesis in female A/J mice. Lung tumors were induced by the tobacco-specific carcinogen, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) administered in drinking water for 7 weeks in mice maintained on an AIN-76A semi-synthetic diet. Propolis granular A. P. C (100 mg/kg body wt.) was administered orally daily for 6 days/week from 1 week before NNK administration and throughout the experiment. Sixteen weeks after the NNK treatment, the mice were killed and the number of surface lung tumors was measured. The number of lung tumors in mice treated with NNK alone for 7 weeks (9.4 mg/mouse) was significantly more than in that observed in control mice. Propolis granular A. P. C significantly decreased the number of lung tumors induced by NNK. These results indicate that propolis granular A. P. C is effective in suppressing NNK-induced lung tumorigenesis in mice.
