Unilateral radiation pneumonitis in sheep: Physiological changes and bronchoalveolar lavage

Journal Article · Tue Feb 28 23:00:00 EST 1989 · Journal of Applied Physiology (Bethesda, Maryland); (USA)

OSTI ID:5513112

Tillman, B F; Loyd, J E; Malcolm, A W; Holm, B A; Brigham, K L ^[1]

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1. Vanderbilt Univ. School of Medicine, Nashville, TN (USA)

Radiation pneumonitis is a life-threatening result of therapeutic thoracic irradiation, yet its mechanisms are poorly understood. We studied the effects of unilateral lung irradiation (3,000 rad) in sheep from the immediate response to the later development of radiation pneumonitis. We defined radiation pneumonitis by its diagnostic clinical feature, radiographic infiltration of the irradiated zone with a straight margin corresponding to the radiation port. The immediate response in the few hours after irradiation was characterized by cough, labored respiration, hypoxemia (arterial PO{sub 2} decreased 19 Torr), mild pulmonary hypertension (pulmonary arterial pressure increased 20%), and lymphopenia. Hemodynamics and gas exchange returned to normal by day 2 but became abnormal again before or during radiation pneumonitis at 32 +/- 2 days. Respiratory distress, hypoxemia, and pulmonary hypertension recurred during radiation pneumonitis. Bronchoalveolar lavage during radiation pneumonitis contained increased neutrophils (19 +/- 4%, control = 7%), increased protein (0.27 +/- 0.1 g/dl, control = 0.12 +/- 0.03), and severely impaired ability to lower surface tension. Alveolar macrophages from both lungs during unilateral radiation pneumonitis exhibited impaired generation of superoxide after phorbol myristate (only a 30% increase). Normal control alveolar macrophages increased superoxide production after stimulation greater than 400%. We conclude that unilateral lung irradiation in sheep causes a mild immediate response followed by radiation pneumonitis at 1 mo. Unilateral radiation pneumonitis in this model is associated with ipsilateral neutrophilic alveolitis, increased bronchoalveolar lavage protein, and impaired surfactant function, as well as bilateral functional abnormalities of alveolar macrophages.

• OSTI ID: 5513112
• Journal Information: Journal of Applied Physiology (Bethesda, Maryland); (USA), Journal Name: Journal of Applied Physiology (Bethesda, Maryland); (USA) Vol. 66:3; ISSN 8750-7587; ISSN JAPYA
• Country of Publication: United States
• Language: English

Related Subjects

560152* -- Radiation Effects on Animals-- Animals
560300 -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMAL CELLS
ANIMALS
BIOLOGICAL EFFECTS
BIOLOGICAL MATERIALS
BIOLOGICAL MODELS
BLOOD
BLOOD CELLS
BLOOD PRESSURE
BODY
BODY FLUIDS
BRONCHI
CARCINOGENS
CONNECTIVE TISSUE CELLS
DOMESTIC ANIMALS
ELEMENTS
ESTERS
LEUKOCYTES
LUNGS
MACROPHAGES
MAMMALS
MATERIALS
NEUTROPHILS
NONMETALS
ORGANIC COMPOUNDS
ORGANS
OXYGEN
PHAGOCYTES
PHORBOL ESTERS
PNEUMONITIS
RADICALS
RADIOINDUCTION
RESPIRATORY SYSTEM
RUMINANTS
SHEEP
SOMATIC CELLS
SUPEROXIDE RADICALS
VERTEBRATES