No effect of the angiotensin receptor blocker candesartan on cerebrovascular autoregulation in rats during very high and low sodium intake

TY - JOUR

T1 - No effect of the angiotensin receptor blocker candesartan on cerebrovascular autoregulation in rats during very high and low sodium intake

AU - Sigurdsson, Sigurdur T.

AU - Bie, Peter

AU - Nielsen, Arne H.

AU - Strandgaard, Svend

AU - Paulson, Olaf B.

PY - 2019/7

Y1 - 2019/7

N2 - Autoregulation of cerebral blood flow (CBF) denotes that CBF is constant despite fluctuation of blood pressure within wide limits. Inhibition of the renin–angiotensin system (RAS) is known to decrease the lower and upper limits of CBF autoregulation. We have previously shown that this includes inhibition by the angiotensin receptor blocker (ARB) candesartan. In the present study we investigated the influence of the ARB candesartan on the lower limit of CBF autoregulation in two groups of Sprague-Dawley rats, on high (4.0% Na+) and low (0.004% Na+) sodium diet, respectively. Control animals were given the same diet, but no ARB. CBF was studied with the laser Doppler method. Blood pressure was lowered by controlled bleeding. Results revealed that both high and low sodium diet with low and high renin levels respectively block the influence of candesartan on CBF autoregulation. This was expected in rats on a high salt diet with a low renin level, but unexpected in rats with a low salt intake with a high renin level.

AB - Autoregulation of cerebral blood flow (CBF) denotes that CBF is constant despite fluctuation of blood pressure within wide limits. Inhibition of the renin–angiotensin system (RAS) is known to decrease the lower and upper limits of CBF autoregulation. We have previously shown that this includes inhibition by the angiotensin receptor blocker (ARB) candesartan. In the present study we investigated the influence of the ARB candesartan on the lower limit of CBF autoregulation in two groups of Sprague-Dawley rats, on high (4.0% Na+) and low (0.004% Na+) sodium diet, respectively. Control animals were given the same diet, but no ARB. CBF was studied with the laser Doppler method. Blood pressure was lowered by controlled bleeding. Results revealed that both high and low sodium diet with low and high renin levels respectively block the influence of candesartan on CBF autoregulation. This was expected in rats on a high salt diet with a low renin level, but unexpected in rats with a low salt intake with a high renin level.

KW - autoregulation

KW - cerebral blood flow

KW - laser Doppler flow measurement

KW - Renin–angiotensin system

KW - sodium intake

U2 - 10.1177/1470320319874615

DO - 10.1177/1470320319874615

M3 - Journal article

C2 - 32154769

AN - SCOPUS:85073208491

SN - 1470-3203

VL - 20

SP - 1

EP - 6

JO - JRAAS - Journal of the Renin-Angiotensin-Aldosterone System

JF - JRAAS - Journal of the Renin-Angiotensin-Aldosterone System

IS - 3

ER -