RESUMO
Here we developed a model of chronic thromboembolic pulmonary hypertension (CTEPH) using repeated intravenous administration of microencapsulated thrombi with a controlled rate of biodegradation. Autologous thrombi encapsulated in alginate microspheres with a diameter of 190±48 µm were intravenously injected to rats 8 times every 4 days. In the comparison group, nonmodified thrombi were injected. After 6 weeks, a significant increase in systolic pressure in the right ventricle, a decrease in exercise tolerance, and an increase in the index of vascular wall hypertrophy were revealed in the group receiving injections of microencapsulated thrombi in comparison with the group receiving nonmodified thrombi and healthy animals. Thus, the developed representative CTEPH model can be used to test promising pharmacological substances.
Assuntos
Hipertensão Pulmonar , Embolia Pulmonar , Animais , Ratos , Hipertensão Pulmonar/metabolismo , Artéria Pulmonar/metabolismo , Embolia Pulmonar/metabolismo , Doença CrônicaRESUMO
It is established that the x-ray contrast agents urografin (76 %), omnipaque-300, optiray-350, ultravist-300, and visipaque-270 produce a dose-dependent decrease in the deformation properties of human erythrocytes in vitro. The degree of manifestation of this negative influence increases with the osmotic activity of agents in the following order: visipaque = ultravist < or = omnipaque < or = optiray < urografin. The effect of these x-ray contrast agents on the deformation of erythrocytes is reversible. Erythrocytes restore their normal deformation properties upon removal of the osmotic pressure induced by the x-ray contrast agents.