Cardiovascular and cerebrovascular responses to acute hypoxia following exposure to intermittent hypoxia in healthy humans

Julien Brugniaux, Glen E. Foster, Vincent Pialoux, Cailean T. C. Duggan, Patrick J. Hanly, Sofia B. Ahmed, Marc J. Poulin

Research output: Contribution to journalArticlepeer-review


Intermittent hypoxia (IH) is thought to be responsible for many of the long-term cardiovascular consequences associated with obstructive sleep apnoea (OSA). Experimental human models of IH can aid in investigating the pathophysiology of these cardiovascular complications. The purpose of this study was to determine the effects of IH on the cardiovascular and cerebrovascular response to acute hypoxia and hypercapnia in an experimental human model that simulates the hypoxaemia experienced by OSA patients. We exposed 10 healthy, male subjects to IH for 4 consecutive days. The IH profile involved 2 min of hypoxia (nadir inline image= 45.0 mmHg) alternating with 2 min of normoxia (peak inline image= 88.0 mmHg) for 6 h. The cerebral blood flow response and the pressor responses to hypoxia and hypercapnia were assessed after 2 days of sham exposure, after each day of IH, and 4 days following the discontinuation of IH. Nitric oxide derivatives were measured at baseline and following the last exposure to IH. After 4 days of IH, mean arterial pressure increased by 4 mmHg (P < 0.01), nitric oxide derivatives were reduced by 55% (P < 0.05), the pressor response to acute hypoxia increased (P < 0.01), and the cerebral vascular resistance response to hypoxia increased (P < 0.01). IH alters blood pressure and cerebrovascular regulation, which is likely to contribute to the pathogenesis of cardiovascular and cerebrovascular disease in patients with OSA.
Original languageEnglish
Pages (from-to)3287 - 3299
Number of pages12
JournalJournal of Physiology
Issue number13
Publication statusPublished - 1 Jul 2009


  • cardiovascular and cerebrovascular disease
  • Intermittent Hypoxia (IH)
  • obstructive sleep apnea (OSA)
  • cerebrovascular regulation


Dive into the research topics of 'Cardiovascular and cerebrovascular responses to acute hypoxia following exposure to intermittent hypoxia in healthy humans'. Together they form a unique fingerprint.

Cite this