The Protective Effects of Gadolinum Chloride on Pneumotoxic Effects of Styrene in Rat

OBJECTIVE The aim of the present study was to evaluate the protective effects of gadoli- num on pneumotoxic effects of styrene in rats as an experimental model. MATERIALS AND METHODS In this experimental study a total number of 40 adult male Sprague Dawley rats that weighed 200 ± 13 g were randomly divided into five groups: i. styrene (St, N=10), ii. styrene+gadolinium chloride (GdCl3, N=10), iii. control (N=10), iv. GdCl3 (N=5) and v. normal saline (Nor.Sal, as a solvent of GdCl3, N=5). Normal saline, as a sham control group, was otherwise treated identically. Rats from the experimental groups were exposed to St in an exposure chamber for 6 days/week, 4 hours/day for up to 3 weeks. At the end of the experi- ment, rats from all groups were killed by deep anesthesia. Their lungs were removed, then fixed in formalin and weighed. Tissue samples were processed routinely and sections stained by the hematoxylin and eosin (H&E) and periodic acid Schiff (PAS) methods. We measured the thicknesses of the respiratory epithelia and interalveolar septa. Obtained data were ana- lyzed by ANOVA, the Tukey test and the paired t test. RESULTS Shedding of apical cytoplasm in the bronchiole was a prominent feature of the St group. PAS staining revealed histochemical changes in goblet cells in the epithelium of the St group. While there were no significant changes in lung weights and respiratory epithelial thicknesses between all studied groups, statistical analysis showed a significant alteration in the thickness of interalveolar septa in the St and St+GdCl3 group compared to the control groups (P<0.001). CONCLUSION Styrene induced structural and histochemical changes in bronchiole, interalveolar septa and alveolar organization in the rats' lungs. Gadolinium appeared to partially reduce the toxic effects of styrene on the lungs.