TY - JOUR
T1 - Role of intrarenal ANG II in reflex neural stimulation of plasma renin activity and renal sodium reabsorption
AU - Nelson, L. D.
AU - Osborn, J. L.
PY - 1993
Y1 - 1993
N2 - Renal sympathetic stimulation of plasma renin activity (PRA) and sodium reabsorption was examined in conscious dogs before and during intrarenal angiotensin II (ANG II)-type 1 receptor blockade with losartan (Dup-753) and converting enzyme inhibition. In uninephrectomized dogs, renal function and PRA responses to 14% blood volume depletion (BVD) were measured. BVD was utilized to activate renal sympathetic outflow in the absence of hypotension. In eight vehicle-treated dogs, 14% BVD increased PRA from 1.38 ± 0.32 to 2.79 ± 0.66 ng ANG I · ml-1 · h-1 and decreased urinary sodium excretion (U(Na)V) from 85.1 ± 11.3 to 45.4 ± 7.5 μeq/min. During losartan (n = 6) and captopril (n = 5) infusion, plasma renin responses were enhanced in response to 14% BVD (1.93 ± 0.48 to 5.74 ± 2.25 and 3.03 ± 0.73 to 9.19 ± 1.94 ng ANG I · ml-1 · h-1, respectively), whereas antinatriuretic responses were similar to vehicle-infused dogs. Thus, neurogenic antinatriuresis is not mediated by secondary generation of ANG II, since U(Na)V decreased similarly to control in all conditions of ANG II blockade. Tonic intrarenal and/or circulating ANG II synthesis of dogs on a normal sodium diet inhibit neurogenic stimulation of renin release, since PRA responses were enhanced after blockade of ANG II.
AB - Renal sympathetic stimulation of plasma renin activity (PRA) and sodium reabsorption was examined in conscious dogs before and during intrarenal angiotensin II (ANG II)-type 1 receptor blockade with losartan (Dup-753) and converting enzyme inhibition. In uninephrectomized dogs, renal function and PRA responses to 14% blood volume depletion (BVD) were measured. BVD was utilized to activate renal sympathetic outflow in the absence of hypotension. In eight vehicle-treated dogs, 14% BVD increased PRA from 1.38 ± 0.32 to 2.79 ± 0.66 ng ANG I · ml-1 · h-1 and decreased urinary sodium excretion (U(Na)V) from 85.1 ± 11.3 to 45.4 ± 7.5 μeq/min. During losartan (n = 6) and captopril (n = 5) infusion, plasma renin responses were enhanced in response to 14% BVD (1.93 ± 0.48 to 5.74 ± 2.25 and 3.03 ± 0.73 to 9.19 ± 1.94 ng ANG I · ml-1 · h-1, respectively), whereas antinatriuretic responses were similar to vehicle-infused dogs. Thus, neurogenic antinatriuresis is not mediated by secondary generation of ANG II, since U(Na)V decreased similarly to control in all conditions of ANG II blockade. Tonic intrarenal and/or circulating ANG II synthesis of dogs on a normal sodium diet inhibit neurogenic stimulation of renin release, since PRA responses were enhanced after blockade of ANG II.
KW - angiotensin II
KW - losartan
KW - neural control of kidney
KW - plasma renin activity
KW - urinary sodium excretion
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U2 - 10.1152/ajpregu.1993.265.2.r392
DO - 10.1152/ajpregu.1993.265.2.r392
M3 - Article
C2 - 8368393
AN - SCOPUS:0027254874
SN - 0002-9513
VL - 265
SP - R392-R398
JO - American Journal of Physiology - Regulatory Integrative and Comparative Physiology
JF - American Journal of Physiology - Regulatory Integrative and Comparative Physiology
IS - 2 34-2
ER -