INTRODUCTION: Smoking is a serious worldwide public health problem. Animal models act as a bridge between laboratory and human studies. The models applied are difficult to reproduce because of the use of different types of inhalation chambers and mainly because of the lack of continuous monitoring of smoke concentration. OBJECTIVE: To develop an inhalation chamber for rats (with only the nose exposed) in which the amount of carbon monoxide (CO) can be maintained and monitored constantly. MATERIAL AND METHODS: Male Wistar rats weighing 250g were exposed to 50ppm CO produced by the smoke from a filter-free cigarette. The animals were submitted to a single 2-h exposure and then sacrificed at 0, 4, 24 and 48h. The control group was left restrained inside the small perpendicular chambers, receiving only 5L/min of compressed air. RESULTS: The model was able to increase HbCO levels immediately after the end of exposure (p<0.001), with a decrease being observed from 2h onwards when compared to the levels of the control group. Plasma cotinine increased immediately after exposure, and showed still detectable levels at 2 and 4h (p<0.05). CONCLUSION: We conclude that the presented inhalation chamber system is able to maintain a controlled CO concentration in a model in which small animals are exposed to the inhalation of cigarette smoke, permitting well-controlled studies, as well as investigations involving other toxic gases and air pollutants. 2008 SEPAR. Published by Elsevier Espana. All rights reserved.
INTRODUCTION: Smoking is a serious worldwide public health problem. Animal models act as a bridge between laboratory and human studies. The models applied are difficult to reproduce because of the use of different types of inhalation chambers and mainly because of the lack of continuous monitoring of smoke concentration. OBJECTIVE: To develop an inhalation chamber for rats (with only the nose exposed) in which the amount of carbon monoxide (CO) can be maintained and monitored constantly. MATERIAL AND METHODS: Male Wistar rats weighing 250g were exposed to 50ppm CO produced by the smoke from a filter-free cigarette. The animals were submitted to a single 2-h exposure and then sacrificed at 0, 4, 24 and 48h. The control group was left restrained inside the small perpendicular chambers, receiving only 5L/min of compressed air. RESULTS: The model was able to increase HbCO levels immediately after the end of exposure (p<0.001), with a decrease being observed from 2h onwards when compared to the levels of the control group. Plasma cotinine increased immediately after exposure, and showed still detectable levels at 2 and 4h (p<0.05). CONCLUSION: We conclude that the presented inhalation chamber system is able to maintain a controlled CO concentration in a model in which small animals are exposed to the inhalation of cigarette smoke, permitting well-controlled studies, as well as investigations involving other toxic gases and air pollutants. 2008 SEPAR. Published by Elsevier Espana. All rights reserved.
Authors: Rodrigo de las Heras Kozma; Edson Marcelino Alves; Valter Abraão Barbosa-de-Oliveira; Fernanda Degobbi Tenorio Quirino dos Santos Lopes; Renan Cenize Guardia; Henrique Vivi Buzo; Carolina Arruda de Faria; Camila Yamashita; Manzelio Cavazzana Júnior; Fernando Frei; Maria José de Oliveira Ribeiro-Paes; João Tadeu Ribeiro-Paes Journal: J Bras Pneumol Date: 2014 Jan-Feb Impact factor: 2.624