Effect of bronchopulmonary lavage on lung retention and clearance of particulate material in hamsters.

Abstract

Hamsters were exposed to an arosol of fused a inosilcat particles (FAP) labeled with 57Co Three groUpS ofanimalS were given bronchopulmonry laage, beging at either 1 week, 1 month, or 6 months after exposure. Each treated group was lavaged eight times over a period of25 days. Each lavage involved 10 saline washes ofthe lungs. For each group, about 60-70% ofthe body content of 5Co at the startof lavage treatment was removed; nearly half of this was recovered in the first two lavages. A positive correlation was demonstrated between the macrophage content and 57Co activity of the washings The subsequent fractional darance te of57Co from laVaged animals was not significantly different from that in a group of untreated control animals.

Efficient Elimination of Inhaled Nanoparticles from the Alveolar Region: Evidence for Interstitial Uptake and Subsequent Reentrainment onto Airways Epithelium

“…Interestingly this lavageable NP fraction declined to < 0.2 of the totally retained NPs over time. These fractions were much lower than the 0.8 fractions reported in studies using micron-sized particles (Ellender et al 1992; Lehnert et al 1989). In contrast, the daily cleared NP fractions in larynx and fecal excretions were similar to those measured for micron-sized particles as dicussed earlier (Semmler et al 2004).…”

“…This is in clear contrast to the lavaged polystyrene particle (PSL) fractions in AMs, with a range of 0.8 of the lung burden as determined by Lehnert et al (1989; Figure 4). In a comparable study on Syrian hamsters, Ellender et al (1992) obtained fractions in BAL similar to those in the Lehnert study after the inhalation of glassy micron-sized glass particles.…”

“…In the study by Lehnert et al, the lavageable fraction of 2-μm-sized instilled polystyrene particles was quantitatively distinguished from the nonlavageable fraction at various times during 6 months, which indicated that the vast amount of particles stay at all times on the lung epithelium; this was achieved by dissolving tissue, then counting the fluorescent particles. In a similar study in Syrian golden hamsters, Ellender et al (1992) obtained similar results after the hamsters inhaled micron-sized glass particles.…”

Age-dependent changes in porcine alveolar macrophage function during the postnatal period of alveolarization

“…It is difficult to compare activation in the in vivo and in vitro state, but the rate of protein synthesis in rabbit AMs suggests that lavage may result in partial activation [38]. On the other hand, in hamsters, clearance from lavaged animals was not significantly different from that of controls [39]. We do not believe that age-dependent bias in the region of the lung lavaged was a factor within the two-week timeframe of our study, given that the lungs are already quite structurally advanced at birth and the relatively large lavage volumes used.…”

Translocation of Inhaled Nanoparticles

“…In general, MPs remain on the epithelial surface in airways and alveoli of rodents and are accessible to bronchoalveolar lavage (BAL) over several months of retention (Lehnert et al, 1989 ;Ellender et al, 1992 ). Their retention half -lives vary between 60 -80 days at MP doses under physiological conditions; note that retention half -lives increase drastically under particle overload conditions (Morrow, 1988(Morrow, , 1992.…”