The alveolar septal thickness and type II pneumocytes number in irradiated lungs, time expression and the effect of pentoxifylline.
OBJECTIVE
We studied the relationship between type II pneumocytes number and alveolar septal thickness during different time after sublethal whole-thorax irradiation of rats and we investigated the influence of pentoxifylline (TNF-alpha inhibitor).


METHODS
Wistar rats were exposed to 15 Gy thoracic irradiation and pentoxifylline (35 mg/kg) twice a week. Lungs were examined histologically and immunohistochemically at intervals ranging from 1-12 weeks and alveolar septal thickness, number of type II pneumocytes (identified by immunoreactivity for cytokeratin 18), and neutrophile granulocytes were counted.


RESULTS
Significant increase of alveolar septal thickness and type II pneumocytes depletion 3 weeks after irradiation were found. Correlation of these markers was r = -0.759. Pentoxifylline significantly inhibits increased alveolar septal thickness without the influence on type II pneumocytes number. Neutrophil penetration started 5 weeks after irradiation in non-treated animals, 8 weeks after irradiation in PTX-treated rats.


CONCLUSIONS
We suggest that pneumocytes depletion is linked to increased vascular permeability, and pentoxifylline therapy does not influence on pneumocytes kinetics after irradiation.
Osterreicher
J
J
Department of Radiobiology and Immunology, Purkynĕ Military Medical Academy, Hradec Králové. osterreicher@pmfhk.cz
Mokry
J
J
Navrátil
L
L
Knízek
J
J
Vávrová
J
J
Skopek
J
J
Macela
A
A
D000818:Animals; D007150:Immunohistochemistry; D007633:Keratins / Q000032:analysis; D008168:Lung / Q000737:chemistry / Q000187:drug effects / Q000473:pathology* / Q000528:radiation effects*; D008297:Male; D010431:Pentoxifylline / Q000494:pharmacology*; D011650:Pulmonary Alveoli / Q000187:drug effects / Q000473:pathology* / Q000528:radiation effects; D017564:Radiation Pneumonitis / Q000473:pathology; D051381:Rats; D017208:Rats, Wistar; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors; D014665:Vasodilator Agents / Q000494:pharmacology*
D014409:Tumor Necrosis Factor-alpha; D014665:Vasodilator Agents; D007633:Keratins; D010431:Pentoxifylline