Exercise increases the lung clearance of inhaled Tc-99m DTPA
It has been suggested that blood flow have little effect on the lung clearance of Tc-99m DTPA which depends on the alveolar distension. However an increase of pulmonary blood flow, induces a recruitment of new vascular areas which can enhance this clearance. To assess this hypothesis the pulmonary apical and basal clearances of a sumicronic aerosol of Tc-99m DTPA were studied at rest and at exercise in seven non smoking volunteers in upright posture. As a matter of fact exercising upright is known to increase primarily the apical blood flow. After inhalation the subjects were seated on a bicycle their back against a gamma camera which was linked to a computer. The lung radioactivity was registered successively during a resting and an exercising period. At rest there was a gradient of clearance from the apex to the base of the lung, the apical clearance being significantly higher. At exercise (50 Watts, 60 c. min /sup -1/, 7 min.) this regional gradient was enhanced by a large and significant increase of the apical clearances (0.0340 min /sup -1/ +-0.0063 SD versus 0.00183 min /sup -1/ +- 0.074 SD at rest, n = 7, p < 0.01). By contrast the changes of the basal clearances were slight and unsignificant (0.0146 min /sup -1/ +- 0.0062 SD versus 0.0140 min /sup -1/ +- 0.0082 SD). Since exercise induces little distension of the apical alveoli but drastically enhances the apical blood flow, the observed increase of the apical lung clearance could be primarily attributed to the recruitment of new capillaries induced by exercise in the apices. This led to an increase of the surface area permeability product.
- Research Organization:
- Departement de Medecine Nucleaire Hopital, Henri Mondor 94000 Creteil
- OSTI ID:
- 6706346
- Report Number(s):
- CONF-850611-
- Journal Information:
- J. Nucl. Med.; (United States), Journal Name: J. Nucl. Med.; (United States) Vol. 26:5; ISSN JNMEA
- Country of Publication:
- United States
- Language:
- English
Similar Records
Effects of sustained exercise on pulmonary clearance of aerosolized sup 99m Tc-DTPA
Lung clearance of inhaled /sup 99m/Tc-DTPA in the dog
Related Subjects
62 RADIOLOGY AND NUCLEAR MEDICINE
AEROSOL MONITORING
AEROSOLS
AIR POLLUTION MONITORING
AMINO ACIDS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BLOOD CIRCULATION
BLOOD VESSELS
BODY
CAPILLARIES
CARBOXYLIC ACIDS
CARDIOVASCULAR SYSTEM
CHELATING AGENTS
CLEARANCE
COLLOIDS
COMPUTER GRAPHICS
DETECTION
DIAGNOSTIC TECHNIQUES
DIAGNOSTIC USES
DISPERSIONS
DRUGS
DTPA
EXCRETION
EXERCISE
FLOW RATE
GAMMA DETECTION
HOURS LIVING RADIOISOTOPES
INHALATION
INTAKE
INTERMEDIATE MASS NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
LUNG CLEARANCE
LUNGS
MONITORING
NUCLEI
ODD-EVEN NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANS
PERMEABILITY
RADIATION DETECTION
RADIOACTIVITY
RADIOISOTOPES
RADIONUCLIDE ADMINISTRATION
RADIOPROTECTIVE SUBSTANCES
RESPIRATION
RESPIRATORY SYSTEM
SOLS
TECHNETIUM 99
TECHNETIUM ISOTOPES
TIME DEPENDENCE
USES
YEARS LIVING RADIOISOTOPES