Two mechanisms contribute in the development of pulmonary hypertension in pulmonary embolism (PE) - obstruction of pulmonary blood vessels and vasoconstriction. We hypothesize that hypoxia, increased shear stress and/or activation of gathered leukocytes in the PE may cause a release of reactive oxygen species (ROS). Therefore our aim was to determine the influence of the ROS scavenger Tempol on pulmonary hypertension and to describe NO synthase activity and production of NO oxidative products (NOx) after PE. In general anesthesia sephadex microspheres suspended in PSS were applied in right jugular vein as the pulmonary microembolism. Than we measured in isolated salt solution-perfused lungs the changes in perfusion pressure, activity of NO synthase and NOx plasma concentration in 7 groups of rats: C: control group (n=5), CN: C + sodium nitroprusside (SN) (n=5), EN: PE + SN (n=5), ETN: Tempol + PE + SN (n=5), CL: C + L-NAME (n=5), EL: PE + L-NAME (n=5), ETL: Tempol + PE + L-NAME (n=5). Tempol was applied intraperitoneally before PE. Animals that received Tempol (groups TN, TL) had significantly lower basal perfusion pressure than those which did not receive Tempol (EN, EL). Overall we measured a higher decrease of perfusion pressure than in the control group (C) after application of SN. Administration of L-NAME after PE (EL) increased the pressure more than in the control group (NL). NOx concentration was higher after PE. We found that preventive administration of Tempol decreases the increase in perfusion pressure after PE. PE increased NO release and concentration of NOx.

• MeSH
• aktivace enzymů účinky léků   fyziologie   MeSH
• cyklické N-oxidy farmakologie   terapeutické užití   MeSH
• krevní tlak účinky léků   fyziologie   MeSH
• krysa rodu rattus MeSH
• mikrocirkulace účinky léků   fyziologie   MeSH
• NG-nitroargininmethylester farmakologie   MeSH
• orgánové kultury - kultivační techniky MeSH
• plicní embolie farmakoterapie   metabolismus   MeSH
• plicní oběh účinky léků   fyziologie   MeSH
• potkani Wistar MeSH
• reaktivní formy kyslíku antagonisté a inhibitory   metabolismus   MeSH
• scavengery volných radikálů farmakologie   terapeutické užití   MeSH
• spinové značení MeSH
• synthasa oxidu dusnatého antagonisté a inhibitory   metabolismus   MeSH
• vazokonstrikce účinky léků   fyziologie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

AIM: The aim of the study is to present the feasibility of using dual-energy CT and the evaluation of iodine and air distribution in differentiation of pathological conditions. MATERIAL AND METHOD: We used the data of 50 CT examinations performed due to suspected pulmonary embolism with any pathological finding except consolidation of the parenchyma. The patients underwent CT angiography of the pulmonary arteries on a dual-source CT (DSCT), with the two tubes independently operated at 140 and 80 kV. By exploiting the dual-energy information, iodine distribution maps were obtained in addition to the conventional CT images which served as a marker of pulmonary perfusion. Minimum intensity projections (MinIP) were used as a marker of air content. RESULTS: By comparing the iodine distribution maps and MinIP images, it was possible to differentiate between the following templates of lung parenchyma: A--normal iodine and air distribution; B--iodine content deficit with minimal or with no redistribution of air; C--reduced iodine content and increased content of air; D--deficit of iodine content and increased content of air; E--increased iodine content and normal content of air; F--increased iodine content and reduced content of air; G--reduced perfusion and reduced content of air. The type A (five cases) was typical for the pulmonary embolism with preserved normal conditions of perfusion and ventilation. Type B (18 cases) occurred in pulmonary embolism; type C was found in case of inflammation of small respiratory airways (five cases); emphysema was typical for type D (nine cases); increased perfusion was observed in the parenchyma preserved from emphysema or preserved from embolism in cases of emphysema or pulmonary embolism; type F occurred in pulmonary interstitial edema (four cases) both with pulmonary infection; finally type G was found in interstitial lung diseases (five cases). CONCLUSION: Imaging of the pulmonary circulation by means of dual-energy CT opens the potential to study pathological changes of circulatory and pulmonary perfusion impairments, our presented work signs the important relations between iodine and air distribution which have to be thought in the interpretation of dual-energy perfusion imaging of the lungs.

• MeSH
• angiografie metody   MeSH
• dospělí MeSH
• jod diagnostické užití   farmakokinetika   MeSH
• kontrastní látky farmakokinetika   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• perfuzní zobrazování metody   MeSH
• plicní embolie metabolismus   MeSH
• počítačová rentgenová tomografie metody   MeSH
• rentgendiagnostika - dvourozměrná projekce metody   MeSH
• reprodukovatelnost výsledků MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• senzitivita a specificita MeSH
• vzduch analýza   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH