TY - JOUR
T1 - Cooled neutrophils become deposited in the microcirculation after infusion: A potential mechanism for microvascular disruption following tissue hypothermia
AU - Jetha, KA
AU - Nash, Gerard
AU - Egginton, Stuart
PY - 2008/12/1
Y1 - 2008/12/1
N2 - 1. We examined whether changes in rigidity and adhesiveness of neutrophils exposed to cooling and rewarming observed in vitro might impair microvascular perfusion in vivo. Neutrophils from donor rats were fluorescently (calcein-AM) or radioactively (Indium-111) labelled, incubated at 10 or 37 degrees C in vitro, and infused into recipients. Changes in transit rate and adhesive behaviour within post-capillary venules was quantified in m. extensor digitorum longus (EDL) using intravital microscopy, and tissue distribution determined.
2. There was an increased propensity of cooled cells to undergo adhesion following transfer into the recipient rat. However, cooling had no effect on median transit (354 mu m s(-1)) or rolling (14 mu m s(-1)) velocities during the first 5 min after infusion suggesting that cooling promotes adhesion, but does not delay passage through capillaries. Cooled neutrophils subsequently transformed to stationary adhesion. Their immobilisation was higher than for cells held at 37 degrees C (P <0.05), and once immobilised they remained firmly adherent to the vessel wall. Cooled, radiolabelled neutrophils showed tissue-specific accumulation after 3 min, but were cleared to the same extent as warmed cells by 20 min.
3. Our data suggest that cooling and rewarming of neutrophils impairs their ability to transit microvessels, reflecting changes in adhesive and mechanical properties observed in vitro. and may contribute to cold-associated circulatory pathology. (c) 2008 Elsevier Ltd. All rights reserved.
AB - 1. We examined whether changes in rigidity and adhesiveness of neutrophils exposed to cooling and rewarming observed in vitro might impair microvascular perfusion in vivo. Neutrophils from donor rats were fluorescently (calcein-AM) or radioactively (Indium-111) labelled, incubated at 10 or 37 degrees C in vitro, and infused into recipients. Changes in transit rate and adhesive behaviour within post-capillary venules was quantified in m. extensor digitorum longus (EDL) using intravital microscopy, and tissue distribution determined.
2. There was an increased propensity of cooled cells to undergo adhesion following transfer into the recipient rat. However, cooling had no effect on median transit (354 mu m s(-1)) or rolling (14 mu m s(-1)) velocities during the first 5 min after infusion suggesting that cooling promotes adhesion, but does not delay passage through capillaries. Cooled neutrophils subsequently transformed to stationary adhesion. Their immobilisation was higher than for cells held at 37 degrees C (P <0.05), and once immobilised they remained firmly adherent to the vessel wall. Cooled, radiolabelled neutrophils showed tissue-specific accumulation after 3 min, but were cleared to the same extent as warmed cells by 20 min.
3. Our data suggest that cooling and rewarming of neutrophils impairs their ability to transit microvessels, reflecting changes in adhesive and mechanical properties observed in vitro. and may contribute to cold-associated circulatory pathology. (c) 2008 Elsevier Ltd. All rights reserved.
KW - Rat
KW - Intravital microscopy
KW - EDL
KW - Venules
KW - Leukocytes
KW - Skeletal muscle
U2 - 10.1016/j.jtherbio.2008.08.004
DO - 10.1016/j.jtherbio.2008.08.004
M3 - Article
VL - 33
SP - 451
EP - 458
JO - Journal of Thermal Biology
JF - Journal of Thermal Biology
IS - 8
ER -