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Query: UMLS:C0034067 (emphysema)
 11,506 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Selected morphometric parameters of the lungs and heart of rats with experimental emphysema caused by a proteolytic enzyme--papain have been presented. The morphometric evaluation was carried out after the 1st, 3rd and 6th months following an intratracheal infusion of papain solution. It was found that administration of the papain caused emphysematous changes in the lungs, which intensity measured morphometricly increased until the third month, and then became stable. The first evidence of the right ventricle hypertrophy appeared already in the third month of the experiment. The evident hypertrophy of the muscle of both ventricles and of the interventricular septum was observed after six months of the experiment. Morphologic changes developing in both ventricles suggest an existence of a common pathogenetic factor affecting simultaneously the myocardium of right and left heart ventricles.
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PMID:Cor pulmonale in experimental lung emphysema. I. The morphometric evaluation of pulmonary and myocardium changes. 883 17

Development of ultrastructural changes in the hearts of rats with experimental lung emphysema, induced by proteolytic enzyme--papain, has been analysed. Simultaneous development of changes in the right ventricle muscle and in the subendocardial layer of the heart left ventricle myocardium was observed. After 1 month from papain administration in the muscle cells of the right ventricle a significant increase of mitochondria number and their polymorphism were observed. After 3 and 6 months similar changes were observed in both ventricles, however they were more pronounced in the cells of the right ventricle. Mitochondria showed significant damage in the form of clearning up of matrix and destruction of cristas and breaking of their membranes. An enlarged number of irregular intercalated discs was observed too. 6 months after papain administration in some of the right ventricle muscle cells a significant damage of myofibrils and increase in the number of sarcomeres as well as decrease of mitochondria number in these cells were noticed. Focally proliferation of connective tissue was observed too. The role of hypoxia as an essential factor, responsible for the observed morphologic changes has been discussed.
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PMID:Cor pulmonale in experimental lung emphysema. II. An ultrastructure of myocardium. 883 18

A morphometrical analysis of changes in the heart of rats with experimental lung emphysema due to single intratracheal administration of papain solution has been done. Special attention has been paid to quantitative changes of capillaries and to the cardiomyocyte diameter in respective regions of the myocardium after one, three and six months following the administration of papain. A histological and morphometrical analysis of changes in the lungs has also been carried out and partial pressures of oxygen and carbon dioxide in the arterial blood of the examined animals have been marked. It has been found that a single administration of papain caused emphysematous changes in the lungs, growing more intense until the third month of the experiment. The progression of these changes corresponded to a capillary density increase in the right ventricle, interventricular septum and in the subendocardial layer of the left ventricle. The increase in the number of capillaries was interpreted as the first adaptive stage of cor pulmonale development and explained by the occurrence of angiogenesis. The changes co-existed with a decrease in partial pressure of oxygen in the arterial blood. After six months of the experiment, a reduction in capillary density in the heart regions mentioned above and a simultaneous increase in the cardiomycyte transversal diameter were observed, being the exponents of evident myocardial hypertrophy. Development of ultrastructural changes in the hearts of rats has been analysed too. Simultaneous development of changes in the right ventricle muscle and in the subendocardial layer of the heart left ventricle myocardium was observed. The role of hypoxia as a one of essential factors responsible for the observed morphologic changes has been discussed.
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PMID:Changes of myocardial capillary density in progression of experimental lung emphysema. 891 67

The aim of the paper was to evaluate mutual relations in the system of alveolar macrophage (AM) - type II pneumocyte (PII) - interstitium of alveolar septa, in the course of experimental lung emphysema in rats subjected to BCG vaccine effect. Administration of BCG vaccine resulted in the cumulation of AM within pulmonary alveoli. These cells exhibited morphological features of increased activity. Intratracheal papain injection induced intralobular emphysema changes, partly generalized, in the animal lungs. The emphysematous changes, with domination of interalveolar septum atrophy, were accompanied by focal accumulation of collagen and elastin. Fibroplasia processes were strongly pronounced in BCG- and papain-treated animals. The areas of connective tissue fibres cumulation revealed indistinctness of the boundary line between PII and the interstitium in some places. Anchorage of collagen fibres and microfibrillary structures were observed in the cytoplasm of PII. The morphological examinations of AM - fibroblasts co-cultures as well as the evaluation of the uptake of 3H-thymidine did not show any significant differences between respective co-cultures of fibroblasts and AM isolated both from the lungs of control and experimental animals (treated with BCG or papain, and BCG+papain). However, a significant growth was noted in 3H-thymidine uptake between fibroblast cultures realized with or without cells isolated from the lungs. The results obtained suggest the possibility of active participation of PII and AM in fibroplasia processes in the course of lung rebuilding after papain administration and in pathological states of the pulmonary tissue, particularly when they are accompanied by increased activity of alveolar macrophages. They also support the inflammatory-repair hypothesis in the development of emphysematous changes.
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PMID:The contribution of type II pneumocytes and alveolar macrophages to fibroplasia processes in the course of enzymatic lung injury. 904 49

A canine model of unilobar papain-induced emphysema was used to examine the extent to which differences in alveolar pressures (PA) would develop between an emphysematous right lower lobe (RLL) and normal left lower lobe (LLL) during forced vital capacity (FVC) deflation. RLL and LLL PA (PARLL and PALLL, respectively) were measured by the alveolar capsule technique. During forced deflation, PA and lobar flows were determined between 95 and 20% FVC. A choke point common to both lower lobes was observed at > 40% FVC. The results showed that deflation compliance (C) was altered for the RLL such that <90% lobar vital capacity, CRLL > CLLL, whereas >90% lobar vital capacity, CRLL < CLLL. At 95 and 90% FVC, the initial RLL PA decline was greater than that for the LLL (P < 0.05). However, large differences in PA were prevented because of the effect of interdependence of regional expiratory flow (IREF). IREF caused a relative decrease in RLL flows and increase in LLL flows that limited PA differences. Between 80 and 50% FVC, as CRLL became greater than CLLL, and because of the initial effect of IREF, PARLL was approximately PALLL. At < and = 40% FVC, without IREF, lobar differences in PA widened. These findings indicate that IREF may affect the dynamics of flow limitation in regional lung disease.
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PMID:Mechanism of lobar alveolar pressure decline during forced deflation in canine regional emphysema. 904 47

The aim of this study was the ultrastructural analysis of the changes in the endothelium of myocardial capillaries and the processes observed in their vicinity in consecutive stages of experimental lung emphysema. Emphysematous changes in the lungs of Wistar rats were induced with a single intraperitoneal infusion of proteolytic enzyme solution, papain, in a dose of 20 mg/kg b.w./0.5 ml PBS. Ultrastructural analysis of the changes within the right ventricle and the subendocardial part of the left ventricle of the heart was made by a transmission electron microscope after 1, 3 and 6 months following papain administration. Special attention was paid to the analysis of changes found in the vicinity of newly formed myocardial capillaries. Animals killed after 1 and 3 months following papain infusion showed blurred borderline between the endothelium of the newly formed myocardial capillaries and perivascular connective matrix. The new vessels had poorly developed basement membrane. Fibrillary structures and/or collagen fibrils were found instead. The latter frequently demonstrated features of disorders in the structure and spatial distribution. Neither fibroblasts nor their processes were observed in the vicinity of the new collagen fibrils. Pericytes were occasionally present. In the later period (6 months from intratracheal papain infusion) well formed collagen fibres dominated in the vicinity of myocardial capillaries. The results of the ultrastructural analysis suggest the possibility of active contribution of endothelial cells to the processes of perivascular fibrosis within the myocardium in the course of experimental lung emphysema.
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PMID:Contribution of capillary endothelium to cor pulmonale development in experimental lung emphysema. 916 20

We examined how the changes in the acini caused by emphysema affected gas transfer out of the acinus (Taci) and lung and chest wall mechanical properties. Measurements were taken from five dogs before and 3 mo after induction of severe bilateral emphysema by exposure to papain aerosol (170-350 mg/dose) for 4 consecutive wk. With the dogs anesthetized, paralyzed, and mechanically ventilated at 0.2 Hz and 20 ml/kg, we measured Taci by the rate of washout of 133Xe from an area of the lung with occluded blood flow. Measurements were repeated at positive end-expiratory pressures (PEEP) of 10, 5, 15, 0, and 20 cmH2O. We also measured dynamic elastances and resistances of the lungs (EL and RL, respectively) and chest wall at the different PEEP and during sinusoidal forcing in the normal range of breathing frequency and tidal volume. After final measurements, tissue sections from five randomly selected areas of the lung each showed indications of emphysema. Taci during emphysema was similar to that in control dogs. EL decreased by approximately 50% during emphysema (P < 0.05) but did not change its dependence on frequency or tidal volume. RL did not change (P > 0.05) at the lowest frequency studied (0.2 Hz), but in some dogs it increased compared with control at the higher frequencies. Chest wall properties were not changed by emphysema (P > 0.05). We suggest that although large changes in acinar structure and EL occur during uncomplicated bilateral emphysema, secondary complications must be present to cause several of the characteristic dysfunctions seen in patients with emphysema.
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PMID:Respiratory impedances and acinar gas transfer in a canine model for emphysema. 921 62

The studies were performed basing on the experimental model of acute pulmonary tissue injury. Papain in a dose of 2 mg/ml PBS/100 g b.w. was administered once, intratracheally, on the 21st day of the experiment. Besides, female Wistar rats were injected twice with BCG vaccine in a dose of 4 x 10(8) microorganisms. BCG vaccine was administered intraperitoneally on the 1st and 14th day of the experiment to activate the system of mononuclear phagocytes. Control rats were intratracheally or/and intraperitoneally given PBS solution. All the animals were killed on the 28th, 35th and 42nd day of the experiment. A single intratracheal papain injection induced emphysematous changes in the animal lungs. The changes were accompanied by basement membrane rebuilding and focal collagen and elastin cumulation. An increase in the number of type II alveolar epithelial cells was observed. Anchorage of collagen fibres and microfibrillary structures in the cytoplasm of type II pneumocytes was observed in the BCG- and papain-treated animals. There, the cytoplasmic membrane of type II cells was completely indistinct and the cytoplasm formed processes to penetrate into the connective tissue fibres. The results obtained indicate possible contribution of type II pneumocytes to fibroplasia processes during lung parenchyma rebuilding and suggest the necessity to include fibroplasia elements in the existing definition of emphysema.
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PMID:Ultrastructural analysis of the pneumocyte-interstitium boundary line in the course of enzymatic lung injury. 933 58

The effect of macrophage system activation on the intensity degree of early destructive changes induced with intratracheal infusion of a proteolytic enzyme-papain was evaluated in the paper. The study was carried out on male Wistar rats. BCG vaccine was used as a macrophage system activating substance. Damage degree of the pulmonary tissue was evaluated after 2 hours following papain administration by determining W/D index (wet lungs/dry lungs). Spectrophometric analysis of bronchoalveolar lavages (BAL) was made in order to evaluate the advancement of haemorrhagic alterations in the lungs. Damage to the pulmonary tissue was greater in the animals given BCG vaccine and papain, compared with controls and papain treated animals. Differences in the intensity degree of destructive changes assessed using both the W/D index and haemoglobin content in BAL were statistically significant. The results obtained indicate a particular role of activation of the macrophage system in the development of early destructive changes due to intratracheal administration of proteolytic enzymes and point to the significance of these changes in the morphogenesis of experimental lung emphysema.
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PMID:Evaluation of the effect of macrophage system activation on the intensity degree of early destructive changes in acute enzymatic lung injury. 933 59

After baseline measurements of lung mechanics, effective air space diameter (EAD), and aerosol dispersion (AD), three dogs were exposed to two treatments of aerosolized papain (3 ml of a 4% solution), and measurements were repeated during a 28-wk follow-up period. EAD and AD were measured with boluses of 0.7-micrometer particles of di-2-ethylhexl sebacate, with Pen (i.e., volumetric bolus penetration/total lung capacity) between 0.1 and 0.4. After papain exposure, EAD increased a mean of 28% (P < 0.0001) and AD (Pen = 0.3, 0.4) increased 4-7% (P < 0.03). The progression of injury was indicated by increasing trends in total lung capacity (P < 0.05), residual volume (P < 0.05), and EAD (P = 0.06) through week 18. There was no evidence of disease progression between weeks 18 and 28, whereas some of the data for individual dogs suggested partial recovery from lung injury at week 28. The results show that aerosol probes can detect and characterize mild lung injury in experimental emphysema.
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PMID:Aerosol probes of lung injury in a 28-wk longitudinal study of mild experimental emphysema in dogs. 993 Dec 14


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