Abstract

Orthostatic changes induce temporary loss of circulatory regulation. Feedback systems react to cardiovascular alterations to compensate for the instability. To clarify the existence of anticipatory cardiovascular regulation during active standing, we continuously recorded blood flow velocity (BFV) in the common carotid artery and cerebral blood volume (CBV) in healthy men. The maximum BFV value decreased significantly before standing in the reaction-time condition. The decrease significantly correlated with the change in systolic blood pressure that accompanies upright standing from a supine position. The anticipatory BFV decrease disappeared during self-paced standing, and all BFV parameters significantly declined after the self-paced standing. The CBV recording showed a significant increase in oxyhemoglobin levels before standing in the reaction-time condition. Our study suggests that some feed-forward cardiovascular regulation triggered by central command could be activated before standing, and it may play a functional role in the maintenance of cerebral perfusion during standing.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.