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Disinhibition of the Dorsomedial Hypothalamus Increases the Frequency of Augmented Breaths in the Anesthetized Rat

  • C. R. Reynolds
  • K. Vujisic
  • P. W. Davenport
  • L. F. Hayward
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 605)

The present study was undertaken to identify if activation of the dorsomedial hypothalamus (DMH) elicits augmented breaths (ABs). DMH disinhibition in urethane anesthetized rats produced both an increase in baseline respiratory rate (RR) and an increase in the number of ABs. The increase in RR was associated with a decrease in both the time of inspiration (Ti) and expiration (Te) and the peak change in RR was observed 5 min post DMH activation. In contrast, the increase in ABs was greatest during the first 1.25 min, and both Tis of the ABs did not change significantly from pre-injection values. The Te of the ABs did decrease but remained significantly greater than the Te of the normal breath during DMH disinhibition. Our results support the hypothesis that the central neural pathway involved in the maintenance of normal respiratory pattern may be distinct from pathways involved in the generation of ABs.

Keywords

Respiratory Rate Inspiratory Effort Arterial Chemoreceptor Normal Breath Time Point Zero 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

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Copyright information

© Springer 2008

Authors and Affiliations

  • C. R. Reynolds
    • 1
  • K. Vujisic
    • 1
  • P. W. Davenport
    • 1
  • L. F. Hayward
    • 1
  1. 1.Department of Physiological SciencesUniversity of FloridaUSA

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