Toxic effects of trichloroethylene on the lung

This study aimed to investigate the effect of trichloroethylene on the lung ofalbino rats histopathologically and ultrastructurally. The experimentalanimals were divided into three treated groups. One group was administeredtrichloroethylene as a single dose [2000 mg/kg] intraperitoneally. The secondand third treated groups received trichloroethylene as repeated doses [1000mg/kg] intraperitoneally every other day for two and four weeks, respectively. Light microscopy of lungs of the first group exhibited variable degenerativechanges including lining epithelium of bronchioles. Electron microscopicexamination revealed a dilatation of endoplasmic reticulum, distension ofperinuclear cisternae and disorientation of mitochondria. Lung of the secondand third groups exhibited variable necrotic changes including bronchiolarepithelium and diffuse interstitial fibrosis in the alveolar zone resulting ina thickening of alveolar septa and distortion of lung structure. Electronmicroscopy revealed cellular changes similar to those in the first group, butof varying degrees. Additionally, there were parenchymal changes includingtype II alveolar cells, which had reduced the numbers of lamellar bodies anddistortion of the microvilli. These results demonstrated thattrichloroethylene is pneumotoxic and affects bronchiolar epithelial andalveolar type II cells

Histopathological study of repeated sublethal electrical injuries in albino rats

This work aimed to study histopathological changes resulting after repeatedexposure to sublethal electric shocks in albino rats. The experimentalanimals were divided into three groups: Group I was exposed to electricalstimulations [220 volts for one second] one hour apart/day for one day; Groups II and III were exposed to the same electrical stimulations/day for twoand three successive days, respectively. Lung, heart, brain, liver, kidney, testis and skin [at the site of entry of current] were dissected out andprocessed for paraffin blocks. Sections were stained with hematoxylin and Eosin for histopathological examination. Light microscopy of lung revealedvascular congestion with interalveolar and intraalveolar hemorrhage of varyingdegrees in all groups. Cardiac muscle exhibited petechial hemorrhage in group II [80%] and group III [90%] with focal streaming of nuclei in group III [80%]. Brain tissue exhibited focal petechial hemorrhage and dilatedperivascular spaces in group II [60%] and group III [70%]. Liver exhibitedoccasional hepatocellular necrosis in group III [50%]. Kidney, testicular andskin tissues were within normal limits in all groups