412. Radiat Res. 1991 Jan;125(1):34-40.
Early radiation response of the canine heart and lung.
Gillette SM(1), Powers BE, Orton EC, Gillette EL.
Author information:
(1)Department of Radiology and Radiation Biology, Colorado State University, Fort
Collins 80523.
In this study three groups of four adult beagle dogs were irradiated with a 12-Gy
single dose to the thorax. The fields used were the entire thorax, the entire
thorax with a heart block in place, and the heart with one-third of the lung
volume. The response of the lung was evaluated by cellular and biochemical
analysis of sequential bronchoalveolar lavage fluids, blood gas analysis,
physical examination, and histopathology. Sparing a small volume of lung improved
survival. Cardiac function was evaluated by right heart catheterization,
echocardiography, physical exam, and histopathology. Pulmonary artery pressure
was increased in all dogs, mean systemic artery pressure was decreased in all
dogs, and no difference could be shown among the groups. These effects are likely
secondary to a reduced pulmonary capillary volume. Stroke volume was
significantly deceased in dogs that had their hearts included in the field but
not in dogs with their hearts shielded. This effect was not thought to be
secondary to lung injury. The influence of lung irradiation on cardiac function
was limited to pulmonary hypertension. Pulmonary hypertension may be enhanced by
the release of vasoactive compounds. Pulmonary hypertension may contribute to
radiation-induced heart failure.
PMID: 1986399 [PubMed - indexed for MEDLINE]