Effect of nickel chloride on the lung of male albino rats with evaluation of the possible protective role of vitamin A light and scanning electron microscopy study

ABSTRACT

Nickel chloride is used in stainless steel industries and as a catalyser in catalytic exhausts in new cars for the last ten years. Increased levels of nickel are present in blood of traffic policemen due to its presence as a fuel additive in lead free fuels. The present study aimed to investigate the effects of nickel chloride on the lungs of male albino rats as well as to evaluate the possible protective role of vitamin A. Vitamin A is chosen because it is essential for growth and development of cells especially the respiratory epithelial cells. The animals were divided into 3 groups. Group I [control group], Group II was injected with nickel chloride and Group III was given vitamin A concomitantly with nickel chloride. The experiment was conducted for 28 days. Nickel chloride induced vacuolation of the cells lining the intrapulmonary air passages. The interalveolar septa were thickened and showed cellular infiltration. There was a highly significant increase in the mean number of eosinophils and macrophages. RBCs were demonstrated in the lumina of the intrapulmonary air passages and in the alveolar spaces. Type II pneumocytes showed apparent hyperplasia that was clearly observed in toluidine blue stained semithin sections. Mucous secretion of goblet cells was collected on the surface of the mucosa of the large intrapulmonary air passages. Scanning electron microscopy showed distortion of the cilia, accumulation of mucous secretion in the bronchial lumen and baldness of a large number of the ciliated cells lining the bronchi. Group III rats that received vitamin A together with nickel chloride showed a histological picture nearly similar to the control. In conclusion, Nickel chloride induced serious histological changes in the lungs of male albino rats. These changes could be ameliorated by a concomitant intake of vitamin A. So, attention must be focused on vitamin A and carotinoids as protective measures for the respiratory system