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Intratracheal instillation methods and the distribution of administered material in the lung of the rat.

Hasegawa-Baba Y, Kubota H, Takata A, Miyagawa M - J Toxicol Pathol (2014)

Bottom Line: Intratracheal instillation is widely used for respiratory toxicity tests in experimental animals.However, there are wide variations in the techniques used for instillation, and it is thus difficult to compare the results obtained using different techniques.To examine the effect of instillation methods, we compared the distribution of a test substance in the lungs of rats after intratracheal instillations under various conditions.

View Article: PubMed Central - PubMed

Affiliation: Health Effects Research Group, National Institute of Occupational Safety and Health, Japan, 21-1 Nagao 6-chome, Tama-ku, Kawasaki 214-8585, Japan.

ABSTRACT
Intratracheal instillation is widely used for respiratory toxicity tests in experimental animals. However, there are wide variations in the techniques used for instillation, and it is thus difficult to compare the results obtained using different techniques. To examine the effect of instillation methods, we compared the distribution of a test substance in the lungs of rats after intratracheal instillations under various conditions. Rats received an intratracheal instillation of 0.3 mL of india ink suspension under different conditions as follows: 3 different angles of body restraint, 0° (supine horizontal), 45° (supine head up) and 90° (vertical head up); 2 instillation speeds, high (40 mL/min) and low (4 mL/min); and 2 different devices, a standard bulb-tipped gavage needle and an aerosolizing microsprayer designed for intratracheal instillation. One hour after treatment under these various conditions, rats were sacrificed, and the local distribution of the suspension in the lungs was observed. No animal restrained in the supine head-up or vertical head-up position died from the treatment; however, fatalities were observed when rats were restrained in the supine horizontal position except under high-speed dosing conditions with a microsprayer. Better distribution of the suspension in the lungs was observed in the rats restrained in the supine head-up position after instillation at high speed when compared with other conditions. These results indicated that high-speed instillation to the subject restrained in the supine head-up position is an appropriate condition for performing intratracheal instillation.

No MeSH data available.


Related in: MedlinePlus

Intratracheal instillation in the lungs (1 hour after exposure). Suspension deposition along the alveolar duct is heavy and uneven (H-E staining, bar=200 μm). The deposition patterns obtained using a standard gavage needle (A) and the MicroSprayer (B) are different.
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fig_008: Intratracheal instillation in the lungs (1 hour after exposure). Suspension deposition along the alveolar duct is heavy and uneven (H-E staining, bar=200 μm). The deposition patterns obtained using a standard gavage needle (A) and the MicroSprayer (B) are different.

Mentions: At high magnification, the deposits using both instillation devices were coarse and uneven, and within the region of deposition, alveolar exposure ranged between extremes of absence to complete filling. The patterns of the lung depositions using a standard gavage needle were focal, and the depositions using the MicroSprayer were dispersed (Fig. 8Fig. 8.


Intratracheal instillation methods and the distribution of administered material in the lung of the rat.

Hasegawa-Baba Y, Kubota H, Takata A, Miyagawa M - J Toxicol Pathol (2014)

Intratracheal instillation in the lungs (1 hour after exposure). Suspension deposition along the alveolar duct is heavy and uneven (H-E staining, bar=200 μm). The deposition patterns obtained using a standard gavage needle (A) and the MicroSprayer (B) are different.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4217227&req=5

fig_008: Intratracheal instillation in the lungs (1 hour after exposure). Suspension deposition along the alveolar duct is heavy and uneven (H-E staining, bar=200 μm). The deposition patterns obtained using a standard gavage needle (A) and the MicroSprayer (B) are different.
Mentions: At high magnification, the deposits using both instillation devices were coarse and uneven, and within the region of deposition, alveolar exposure ranged between extremes of absence to complete filling. The patterns of the lung depositions using a standard gavage needle were focal, and the depositions using the MicroSprayer were dispersed (Fig. 8Fig. 8.

Bottom Line: Intratracheal instillation is widely used for respiratory toxicity tests in experimental animals.However, there are wide variations in the techniques used for instillation, and it is thus difficult to compare the results obtained using different techniques.To examine the effect of instillation methods, we compared the distribution of a test substance in the lungs of rats after intratracheal instillations under various conditions.

View Article: PubMed Central - PubMed

Affiliation: Health Effects Research Group, National Institute of Occupational Safety and Health, Japan, 21-1 Nagao 6-chome, Tama-ku, Kawasaki 214-8585, Japan.

ABSTRACT
Intratracheal instillation is widely used for respiratory toxicity tests in experimental animals. However, there are wide variations in the techniques used for instillation, and it is thus difficult to compare the results obtained using different techniques. To examine the effect of instillation methods, we compared the distribution of a test substance in the lungs of rats after intratracheal instillations under various conditions. Rats received an intratracheal instillation of 0.3 mL of india ink suspension under different conditions as follows: 3 different angles of body restraint, 0° (supine horizontal), 45° (supine head up) and 90° (vertical head up); 2 instillation speeds, high (40 mL/min) and low (4 mL/min); and 2 different devices, a standard bulb-tipped gavage needle and an aerosolizing microsprayer designed for intratracheal instillation. One hour after treatment under these various conditions, rats were sacrificed, and the local distribution of the suspension in the lungs was observed. No animal restrained in the supine head-up or vertical head-up position died from the treatment; however, fatalities were observed when rats were restrained in the supine horizontal position except under high-speed dosing conditions with a microsprayer. Better distribution of the suspension in the lungs was observed in the rats restrained in the supine head-up position after instillation at high speed when compared with other conditions. These results indicated that high-speed instillation to the subject restrained in the supine head-up position is an appropriate condition for performing intratracheal instillation.

No MeSH data available.


Related in: MedlinePlus