8.6 ELECTRICAL CAROTID BARORECEPTOR ACTIVATION LOWERS RENAL ARTERY IMPEDANCE AND STIFFNESS IN AN ACUTE CANINE MODEL

DOI

10.1016/j.artres.2009.10.178How to use a DOI?

Abstract

Background: The exact mechanism by which electrical carotid baroreceptor activation (CBA) lowers blood pressure in patients with hypertension has yet to be fully elucidated. Given the central role of the kidneys in blood pressure regulation, the aim of this study was to assess the impact of CBA on renal artery impedance and hemodynamics.

Materials and Methods: Renal artery pressure (P) and flow velocity (U) were measured using an intravascular pressure-velocity wire catheter (Volcano Corp.) in 6 anaesthetized dogs at baseline (BL) and during CBA intended to produce a moderate reduction in mean arterial pressure. Mean flow velocity (Umean), systolic (SBP), diastolic (DBP) and mean pressure (MAP) were derived. Local pulse wave velocity (PWV) was derived from the upstroke of the PU-loops, and wave intensity analysis and wave decomposition was applied to assess (the ratio of) the backward and forward pressure wave (Pb/Pf). Renal artery input impedance was derived.

Results (Table) and discussion: CBA lowered blood pressure and reduced Pf, leading to higher Pb/Pf. CBA lowered the impedance modulus at all frequencies (DC component by 9%; harmonics on average by 28%). PWV concomitantly decreased significantly.

	SBP mmHg	DBP mmHg	MAP mmHg	Umean cm/s	PWV m/s	Pf mmHg	Pb mmHg	Pb/Pf
BL	107.5(11.0)	69.8(15.8)	85.6(14.3)	29.5(5.4)	8.2(2.9)	34.7(6.0)	12.6(2.8)	0.37(0.08)
CBA	89.1(18.9)*	55.4(21.8)*	68.6(21.8)*	27.4(7.7)	5.4(1.7)*	29.3(3.6)*	12.7(2.5)	0.43(0.06)*

mean(standard deviation);

*

P<0.05; paired T-test

Conclusions: In an acute canine model, CBA has a profound effect of decreasing renal artery impedance and stiffness, suggesting that the therapy modulates renal artery tone and may have renoprotective effects by reducing the pulsatile energy in the microcirculation.

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TY  - JOUR
AU  - P. Segers
AU  - D. Wagner
AU  - K. Ludwig
AU  - A.W. Cates
AU  - D. Georgakopoulos
PY  - 2009
DA  - 2009/12/03
TI  - 8.6 ELECTRICAL CAROTID BARORECEPTOR ACTIVATION LOWERS RENAL ARTERY IMPEDANCE AND STIFFNESS IN AN ACUTE CANINE MODEL
JO  - Artery Research
SP  - 160
EP  - 160
VL  - 3
IS  - 4
SN  - 1876-4401
UR  - https://doi.org/10.1016/j.artres.2009.10.178
DO  - 10.1016/j.artres.2009.10.178
ID  - Segers2009
ER  -