Nickel Induced Alteration of Pathophysiology of Lungs in Experimental Rats

Nickel and its compounds are known lung carcinogens, hypoxia mimicking effect of divalent nickel (Ni (II)) plays a crucial role in transformation of cells and the progression of tumours. In this study we aimed to evaluate the possible pathophysiological alterations of lung tissues of rats exposed to nickel sulphate.

For this study 12 male albino rats were randomly divided into two groups: control (placebo), NiSO₄ and given respective interventions for 21 days. % body weight gain, pulmonarysomatic index was calculated. In lung tissue homogenates of all groups of animals, concentration of lipid peroxidation product malondialdehyde (MDA), nitric oxide (NO) and antioxidant l-ascorbic acid was estimated spectrophotometrically and lung tissue histopathological observations were also made.

Our results shows significantly decreased % body weight gain, elevated lung tissue MDA, NO and concomitant decrease of l-ascorbic acid concentration in NiSO₄ treated groups when compared to control group. Histopathological observations of lung tissue sections of NiSO₄ treated group showed eosinophilic oedema fluid filled alveoli, cystic macrophages, thickened interstitial septa, leucocytic infiltration, haemorrhage and acute bronchiolitis.

Our results demonstrate that heavy metal nickel exposure leads to increased pulmonary oxidative and nitrosative stress, decreased concentrations of antioxidants like l-ascorbic acid and histopathological alterations in lungs. So we can conclude that people exposed to heavy metals like nickel may be more prone for lung disorders irrespective of the route of exposure.