Pulmonary clearance of inhaled 99mTc-DTPA: effect of surfactant depletion in rabbits.
We examined the effect of surfactant depletion on the rate of pulmonary clearance of inhaled 99mTc-diethyl-triamino-penta-acetate (DTPA). 99mTc-DTPA was administered as a fine aerosol to four control animals and to four animals after wash-out of pulmonary surfactant. Care was taken to minimize structural damage to the lavaged lungs. Clearance of 99mTc-DTPA was measured over the right lung by external counting. The clearance rate was substantially increased in the lavaged animals compared to the control animals. We conclude that the pulmonary surfactant system is a rate-limiting factor for the absorption of inhaled 99mTc-DTPA. Measurement of the pulmonary clearance of 99mTc-DTPA may provide a new means for studying the pathogenetic role of the surfactant system in a variety of lung diseases.
D000042:Absorption; D000336:Aerosols; D000818:Animals; D008168:Lung / Q000378:metabolism*; D004369:Pentetic Acid / Q000008:administration & dosage / Q000378:metabolism*; D011650:Pulmonary Alveoli / Q000378:metabolism; D011663:Pulmonary Surfactants / Q000502:physiology*; D011817:Rabbits; D013500:Surface Tension; D013667:Technetium / Q000008:administration & dosage / Q000378:metabolism*; D016284:Technetium Tc 99m Pentetate; D007507:Therapeutic Irrigation
D000336:Aerosols; D011663:Pulmonary Surfactants; D013667:Technetium; D004369:Pentetic Acid; D016284:Technetium Tc 99m Pentetate