The quantitative characteristics of histopathological changes in lungs in acute baclofen poisoning

The aim of the study was to quantify the changes in the lungs in acute baclofen poisoning in an animal experiment. Materials and Methods: The study was performed on 20 male Wistar rats weighing 290–350 g and aged 20 weeks. The animals were divided into 4 groups. The reference group of controls included 5 intact rats. The animals of three experimental groups included 5 rats each were treated with baclofen at a dose of 85 mg/kg. The tested rats were euthanized by displacement of cervical vertebrae at 3, 4,5 and 24 hours, respectively. Lung tissue samples were examined by light microscopy using a video system at ×400 magnification. Results: The area of the intraalveolar septi 4,5 hours after baclofen administration was significantly higher than in the reference group of controls. 3 and 4,5 hours after baclofen administration an increase in the area of alveloli was observed, but the increase was insignificant and the area of alveoli returned to the initial size by the 24th hour. 3 and 4,5 hours after baclofen administration a slight decrease in the area of pulmonary parenchima was observed, which also returned to its initial size in 24 hours. The total area of pulmonary microvessels 4,5 hours after baclofen administration was significantly higher than in the control group and 3 hours after baclofen administration. The area of pulmonary microvessels 24 hours after baclofen administration was significantly higher than in the group of controls, 3 or 4,5 hours after baclofen administration. The area of edema increased and was significantly higher 24 hours after baclofen administration. In baclofen poisoning, a certain complex of general pathological processes in lungs develops. There is a circulatory disorder, increased vascular permeability, infiltration of intraaveolar septis. Conclusion: The quantitative assessment of the changes can be used to evaluate severity of general pathological process in acute baclofen poisonings and to determine the exact time of the poisonings.