Lesões do trato respiratório cádmio induzidas – intoxicação por ingestão e pH da água poderiam influenciar sua gênese? : um estudo experimental em ratos

Abstract

Cadmium is a metal that is widely used in industry. Cadmium exposure may result in a variety of pulmonary diseases. No studies have evaluated tracheal damage or even whether cadmium intake can damage the respiratory tract. The aim of this study was to investigate the histopathological changes caused by cadmium poisoning via intake into the respiratory tract and the possible effects of water pH in the genesis of these changes. Ninety male Wistar rats were used and were divided into six groups (n=15): Group A received 400 mg/l cadmium chloride (CdCl2) in the drinking water at a pH of 7.0; group B received CdCl2 (400 mg/l) in the drinking water at a pH of 5.0; group C received CdCl2 (400 mg/l) in the drinking water at a pH of 8.0; group D received water at a pH of 5.0; group E received water at a pH of 8.0; and group F received water at a pH of 7.0. Animals were euthanized after 6 months. Samples of the lung and trachea were removed. The histopathological analysis was performed to evaluate the presence or not of the following parameters: 1. Trachea: inflammatory infiltrate and type of inflammatory cell; tissue congestion; muscle hypertrophy; non-neoplastic lesions of the mucosa; dysplastic lesions; benign and malignant neoplastic lesions; mucus type (acid or basic); and the number of goblet cells; 2. Lung: interstitial inflammatory infiltrate, inflammatory cell type and location; tissue congestion; interstitial fibrosis; emphysema; necrosis of the parenchyma; dysplastic lesions and the presence of benign and malignant neoplastic lesions. Animals exposed to cadmium had a mean of goblet cells in the trachea of 65.83 cells / 6 high-power fields (HPF), while the animals exposed to cadmium had 85.16 cells / 6 HPF (p = 0.012). Pulmonary emphysema occurred in 71.43 to 100% of the cases, while the non-exposed had emphysema in 6.66% to 15.38% of the cases (p <0.001). The respiratory tract is a target for cadmium-related deficits after intake; however, the pH of the water did not influence the development of these lesions.