Avaliação das alterações morfológicas cardíacas secundárias ao enfisema pulmonar: estudo experimental em ratos

Abstract

Abstract:Objective: The purpose of this study is to evaluate the occurrence and repercussions of chemically induced pulmonary emphysema and the morphological alterations present in rats' hearts of post-induction and to follow the progression afterwards.Method: Seventy five rats divided into two groups: papain (N=50) and control (N=25), were submitted to intratracheal spraying of papain and saline solution, respectively, and were evaluated. The animals were sacrificed 30, 60, 90, 120 or 180 days post-spraying. Arterial blood gases and cardiac and pulmonary morphometrical analysis were performed.Results: Papain spraying produced alveolar tissue destruction similar to the morphological alterations observed in pulmonary emphysema. The papain group presented mean alveolar diameter higher than controls in all periods evaluated (p<0.05). Right ventricle wall thickness and interventricular septum did not show significant macroscopic alterations until six months after emphysema induction. The right ventricle area presented enlargement 120 days after induction of pulmonary emphysema, with mean area higher than controls at 120 and 180 days (p=0.001). The left ventricle presented significant cavity area decrease 90 days after induction of the pulmonary emphysema, followed by slight wall thickening.Conclusions: The adopted experimental model was efficient to morphologically induce pulmonary emphysema. The presence of pulmonary emphysema did not provoke morphological changes in the right ventricle wall and interventricular septum. The alveolar destruction induced left ventricular hypertrophy and enlargement of the right ventricle.Descriptors: Pulmonary emphysema, chemically induced. Pulmonary emphysema, physiopathology. Papain, pharmacology. Disease models, animal. Heart ventricle, anatomy & histology.Avaliação das alterações morfológicas cardíacas secundárias ao enfisema pulmonar: estudo experimental em ratos Evaluation of the cardiac morphological alterations secondary to the pulmonary emphysema: experimental study in rats 342 MONTEIRO, R ET AL -Evaluation of the cardiac morphological alterations secondary to the pulmonary emphysema: experimental study in rats Braz

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“…Consolidated data from the literature point towards the existence of myocardial structural lesions resulting from the exposure of animals to extreme low temperature [3][4][5]. More frequently, the structural myocardial lesion described is characterized by vacuolization of mitochondrial cristae and myofilament disarrangement [3][4][5].…”

Lung injury-dependent oxidative status and chymotrypsin-like activity of skeletal muscles in hamsters with experimental emphysema

“…The inexpensive, papain-induced emphysema model results in pulmonary and systemic alterations characteristic of emphysema patients. Ventilatory mechanical alterations, increased residual functional capacity, total lung volume, pulmonary complacence [9], cardiac overload [10], and skeletal muscle mass loss [11] are previously reported emphysema-associated alterations.…”

Fluoxetine effects on mitochondrial ultrastructure of right ventricle in rats exposed to cold stress

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