Abstract
Heterogeneity in superoxide (O2-·) production (as determined by the reduction of nitro blue tetrazolium to a diformazan precipitate), cell volume, and cell spreading were measured from single rat pulmonary alveolar macrophages (PAM). Of the 330 cells that produced O2-· due to stimulation by adherence, the maximum diformazan produced (MAX) varied between 1.8 and 47.2 fmol and the maximum (initial) rate of diformazan production (R) varied between 2.2 and 81.7 x 10-3 fmol/s. Only six PAM of 336 analyzed failed to produce O2-· suggesting that O2-· production is not a specific function of a small subpopulation of PAM but rather that all PAM are capable of producing O2-·. Importantly, O2-· production by single cells showed extensive heterogeneity that did not correlate (r2 < 0.12) with individual cell volumes, suggesting that the observed heterogeneity may not be due to differences in maturation and/or differentiation. However, when the single cell data were grouped into cell volume subfractions small but increasing linear trends (r2 > 0.81) in MAX and R were found. This discrepancy suggests that PAM heterogeneity in O2-· fraction cannot be estimated adequately by measurements on subpopulations of cells.
Original language | English (US) |
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Pages (from-to) | L464-L470 |
Journal | American Journal of Physiology - Lung Cellular and Molecular Physiology |
Volume | 260 |
Issue number | 6 4-3 |
DOIs | |
State | Published - 1991 |
Keywords
- Long-Evans hooded rats
- Single cells
- Superoxide release
ASJC Scopus subject areas
- Physiology
- Pulmonary and Respiratory Medicine
- Physiology (medical)
- Cell Biology