RESUMEN
Introduction: Di-[2-ethylhexyl]-phthalate [DEHP] is present in a wide variety of medical devices. Infants are more susceptible than the general population
Aim of work: To investigate histological and immnohistochemical changes in the lung of newborn rats in response to mothers' exposure
Materials and methods: Twenty nonpregnant adult female albino rats were used. After pregnancy, on the 15[th] day of pregnancy, dams were divided into two equal groups: the control group received corn oil and the treated group received DEHP [500 mg/kg/day] from the 15[th] day of pregnancy and during the 1[st] three weeks of lactation. Fifteen offspring from each group were subdivided into three subgroups, 1, 2, and 3, which were sacrificed at the 2[nd], 7[th], and 21[st] postnatal day, respectively. Lung specimens were processed for light microscope [H and E and immunohistochemical staining of proliferating cell nuclear antigen] and electron microscope examination
Results: H and E-stained sections of treated lung on the 2[nd] day showed variable-sized saccules. Primary septa were significantly thicker than those of the control group. However, on the 7[th] day, focally dilated saccules with thin primary septa were observed. Saccules and secondary septa were fewer than those in the control group. On the 21[st] day, variable-sized alveoli and a significant increase in septal thickness were observed. Immunohistochemically, there was a significant increase in proliferating cell nuclear antigen-positive cells on both the 2[nd] day and the 21[st] day, whereas they decreased on the 7[th] day in comparison with the control group. Ultrastructurally, treated lung on the 2[nd] day showed a saccular wall with many layers of interstitial cells, some with shrunken nuclei, whereas on the 7[th] day, thin septa were observed. Type II pneumocytes and interstitial cells had heterochromatic shrunken nuclei, whereas on the 21[st] day, the presence of macrophages was observed in the lumen. Interstitials cells and type II pneumocytes showed heterochromatic nuclei and marked distortion of organelles
Conclusion: DEHP induced marked histological and immunohistochemical changes in the lung. Alternative plasticizers with less adverse impact could be used. Further studies on the possible protective effect of antioxidants are recommended