Bionic baroreceptor corrects postural hypotension in rats with impaired baroreceptor

Kazuya Hosokawa, Tomomi Ide, Tomoyuki Tobushi, Kazuo Sakamoto, Ken Onitsuka, takafumi sakamoto, Takeo Fujino, Keita Saku, Kenji Sunagawa

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

Background-Impairment of the arterial baroreflex causes orthostatic hypotension. Arterial baroreceptor sensitivity degrades with age. Thus, an impaired baroreceptor plays a pivotal role in orthostatic hypotension in most elderly patients. There is no effective treatment for orthostatic hypotension. The aims of this investigation were to develop a bionic baroreceptor (BBR) and to verify whether it corrects postural hypotension. Methods and Results-The BBR consists of a pressure sensor, a regulator, and a neurostimulator. In 35 Sprague-Dawley rats, we vascularly and neurally isolated the baroreceptor regions and attached electrodes to the aortic depressor nerve for stimulation. To mimic impaired baroreceptors, we maintained intracarotid sinus pressure at 60 mm Hg during activation of the BBR. Native baroreflex was reproduced by matching intracarotid sinus pressure to the instantaneous pulsatile aortic pressure. The encoding rule for translating intracarotid sinus pressure into stimulation of the aortic depressor nerve was identified by a white noise technique and applied to the regulator. The open-loop arterial pressure response to intracarotid sinus pressure (n=7) and upright tilt-induced changes in arterial pressure (n=7) were compared between native baroreceptor and BBR conditions. The intracarotid sinus pressure-arterial pressure relationships were comparable. Compared with the absence of baroreflex, the BBR corrected tilt-induced hypotension as effectively as under native baroreceptor conditions (native,-39±5 mm Hg; BBR,-41±5 mm Hg; absence,-63±5 mm Hg; P<0.05). Conclusions-The BBR restores the pressure buffering function. Although this research demonstrated feasibility of the BBR, further research is needed to verify its long-term effect and safety in larger animal models and humans.

Original languageEnglish
Pages (from-to)1278-1285
Number of pages8
JournalCirculation
Volume126
Issue number10
DOIs
Publication statusPublished - Sep 4 2012

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Bionics
Orthostatic Hypotension
Pressoreceptors
Pressure
Baroreflex
Arterial Pressure
Controlled Hypotension

All Science Journal Classification (ASJC) codes

  • Physiology (medical)
  • Cardiology and Cardiovascular Medicine

Cite this

Bionic baroreceptor corrects postural hypotension in rats with impaired baroreceptor. / Hosokawa, Kazuya; Ide, Tomomi; Tobushi, Tomoyuki; Sakamoto, Kazuo; Onitsuka, Ken; sakamoto, takafumi; Fujino, Takeo; Saku, Keita; Sunagawa, Kenji.

In: Circulation, Vol. 126, No. 10, 04.09.2012, p. 1278-1285.

Research output: Contribution to journalArticle

Hosokawa, Kazuya ; Ide, Tomomi ; Tobushi, Tomoyuki ; Sakamoto, Kazuo ; Onitsuka, Ken ; sakamoto, takafumi ; Fujino, Takeo ; Saku, Keita ; Sunagawa, Kenji. / Bionic baroreceptor corrects postural hypotension in rats with impaired baroreceptor. In: Circulation. 2012 ; Vol. 126, No. 10. pp. 1278-1285.
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