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04:21
Protein Transfection of Mouse Lung
Published on: May 15, 2013
THE ABSORPTION OF PROTEIN SOLUTIONS FROM THE PULMONARY ALVEOLI
C K Drinker1, M F Warren, M Maclanahan
1Department of Physiology, The Harvard School of Public Health, and the Department of Bacteriology, The Harvard Medical School, Boston.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Proteins injected into dog lung alveoli were detected in blood before lymph. Smaller proteins like egg albumin entered the bloodstream faster than larger ones, such as hemoglobin and horse serum.
Area of Science:
- Pulmonary physiology
- Protein absorption
- Immunology
Background:
- Understanding protein transport from lung alveoli is crucial for respiratory medicine.
- Previous research has explored the absorption of various substances through the alveolar membrane.
Purpose of the Study:
- To investigate the rate and pathway of protein absorption from the lung alveoli into the bloodstream and lymphatic system.
- To compare the absorption kinetics of proteins with different molecular sizes.
Main Methods:
- Proteins (horse serum, hemoglobin, egg albumin) were injected into the lung alveoli of dogs.
- Lymphatic drainage was surgically altered by tying right lymphatic entrances and cannulating the thoracic duct.
- Blood and lymph samples were collected and analyzed using immunological methods to detect protein presence.
Main Results:
- Proteins were detected in the blood before appearing in the lymph, with significant time delays for horse serum and hemoglobin (several hours).
- Egg albumin, a smaller protein, was absorbed into the blood capillaries much more rapidly than hemoglobin or horse serum.
- Immunological assays confirmed the presence of injected proteins in circulation.
Conclusions:
- Proteins injected into the lung alveoli primarily enter the bloodstream first, with subsequent, delayed entry into the lymphatic system.
- Protein absorption rate from the alveoli is inversely related to molecular size, with smaller molecules crossing the alveolar-capillary barrier more efficiently.
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