Physiology of a microgravity environment selected contribution: Measuring the response time of pulmonary capillary recruitment to sudden flow changes

Eric M. Jaryszak, William A. Baumgartner, Amanda J. Peterson, Robert G. Presson, Robb W. Glenny, Wiltz W. Wagner

Research output: Contribution to journalArticle

20 Scopus citations


To determine how rapidly pulmonary capillaries recruit after sudden changes in blood flow, we used an isolated canine lung lobe perfused by two pumps running in parallel. When one pump was turned off, flow was rapidly halved; when it was turned on again, flow immediately doubled. We recorded pulmonary capillary recruitment in subpleural alveoli using videomicroscopy to measure how rapidly the capillaries reached a new steady state after these step changes in blood flow. When flow was doubled, capillary recruitment reached steady state in <4 s. When flow was halved, steady state was reached in ∼8 s. We conclude that the pulmonary microcirculation responds rapidly to step changes in flow, even in the capillaries that are most distant from the hilum.

Original languageEnglish (US)
Pages (from-to)1233-1238
Number of pages6
JournalJournal of Applied Physiology
Issue number3
StatePublished - Dec 1 2000



  • Dogs
  • Microcirculation
  • Videomicroscopy

ASJC Scopus subject areas

  • Physiology
  • Endocrinology
  • Orthopedics and Sports Medicine
  • Physical Therapy, Sports Therapy and Rehabilitation

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