ABSTRACT
This study was designed to investigate the pathogenesis of chlorine gas (Cl2) induced acute lung injury and oedema. Isolated blood-perfused rabbit lungs were ventilated either with air (n=7) or air plus 500 parts per million (ppm) of Cl2 (n=7) for 10 min. Capillary pressure, measured by analysing the pressure/time transients of pulmonary arterial, venous and double (both arterial and venous) occlusions, was unchanged in both groups. In Cl2-exposed lungs, the fluid filtration rate increased from -0.228+/-0.25 to 1.823+/-1.23 mL min(-1) x 100 g(-1) (p<0.001) and the filtration coefficient increased from 0.091+/-0.01 to 0.259+/-0.07 mL x min(-1) x cmH2O(-1) x 100 g(-1) (p<0.001). No changes were observed in the control lungs. The extravascular lung water/blood-free dry weight ratio was 8.6+/-1.6 in the Cl2 group and 4.0+/-0.5 in the control group (p<0.001), confirming that the increase in lung weight was related to accumulation of extravascular fluid. Although the alveolar flooding by oedema is explained, in part, by the Cl2-induced epithelial injury, our results suggest that Cl2 exposure induces acute lung injury and oedema due to an increased microvascular permeability.
Subject(s)
Chlorine/toxicity , Respiratory Distress Syndrome/chemically induced , Respiratory Distress Syndrome/physiopathology , Animals , Capillary Permeability/physiology , Chlorine/administration & dosage , Edema/chemically induced , Edema/diagnosis , Edema/physiopathology , Gases/administration & dosage , Gases/toxicity , In Vitro Techniques , Lung/pathology , Pulmonary Artery/physiology , Pulmonary Veins/physiology , Pulmonary Wedge Pressure/physiology , RabbitsABSTRACT
We have perfected a specific and original analytical method suitable for organic and inorganic compounds using sampled run-off water collected nearby a filling station. The dissolved lead species are volatilized by substituting the inorganic ligands with hydrogen, using sodium-borohydride in a suitable reaction medium (H2O2, KOH). The volatile lead hydrides are then trapped on a gas chromatographic column filled with Chromosorb W impregnated with 2% of OV 275 and immersed in liquid nitrogen. After desorption, the products are analysed by atomic absorption spectroscopy. We have carried out the analysis of aldehydes mixtures, sampled from a smog chamber. They are trapped, at room temperature, in a glass column filled with Tenax. These pollutants are then heated at 250 degrees C under a flow of nitrogen, and trapped again in a melted silica capillary column at -110 degrees C. This trapping being over, the column is drastically heated at 200 degrees C, which drives the products into the capillary column of a gas-chromatograph apparatus. This method has also enabled us to carry out a direct analysis of these pollutants sorbed on particles which have been placed into the glass column. this thermodesorption-gas chromatography system, coupled with a mass-spectrometry apparatus, allows us to identify and analyse most atmospheric pollutants.
