TY - JOUR
T1 - Contribution of the renin-angiotensin system and of the sympathetic nervous system to blood pressure homeostasis during chronic restriction of sodium intake
AU - Volpe, Massimo
AU - Lembo, Giuseppe
AU - Alberto, Morganti
AU - Mario, Condorelli
AU - Trimarco, Bruno
PY - 1988
Y1 - 1988
N2 - In a previous paper, we showed that during a long-term, moderate restriction in sodium intake, sympathetic nervous system activity was only transiently stimulated, whereas a sustained rise of plasma renin activity occurred. However, the contribution from stimulation of the renin-angiotensin system in the maintenance of blood pressure homeostasis during a low-salt diet is still unclear.To investigate this issue, in eight normal subjects blood pressure, heart rate, plasma catecholamines, renin activity; and aldosterone were measured during normal sodium intake (150 mEq/d), after converting-enzyme inhibition (enalapril 20 mg/d po), and during one month of sodium intake restriction (50 mEq/d) associated with chronic inhibition of converting-enzyme (CEI). During a low-salt diet with CEI, plasma renin activity rose significantly as a result of CEI. In addition, even in the presence of a marked and sustained increase in plasma norepinephrine and in upright heart rate, a decrease in blood pressure was observed in all the measurements performed during the course of the study as compared to the control values. Our findings support the hypothesis that renin-angiotensin system activation plays an important role in the maintenance of blood pressure homeostasis during a low-salt diet. In fact, in the presence of an effective blockade of angiotensin II formation, blood pressure is decreased, despite the concurrent, sustained stimulation of the sympathetic nervous system.
AB - In a previous paper, we showed that during a long-term, moderate restriction in sodium intake, sympathetic nervous system activity was only transiently stimulated, whereas a sustained rise of plasma renin activity occurred. However, the contribution from stimulation of the renin-angiotensin system in the maintenance of blood pressure homeostasis during a low-salt diet is still unclear.To investigate this issue, in eight normal subjects blood pressure, heart rate, plasma catecholamines, renin activity; and aldosterone were measured during normal sodium intake (150 mEq/d), after converting-enzyme inhibition (enalapril 20 mg/d po), and during one month of sodium intake restriction (50 mEq/d) associated with chronic inhibition of converting-enzyme (CEI). During a low-salt diet with CEI, plasma renin activity rose significantly as a result of CEI. In addition, even in the presence of a marked and sustained increase in plasma norepinephrine and in upright heart rate, a decrease in blood pressure was observed in all the measurements performed during the course of the study as compared to the control values. Our findings support the hypothesis that renin-angiotensin system activation plays an important role in the maintenance of blood pressure homeostasis during a low-salt diet. In fact, in the presence of an effective blockade of angiotensin II formation, blood pressure is decreased, despite the concurrent, sustained stimulation of the sympathetic nervous system.
KW - Blood pressure
KW - Converting-enzyme inhibitor
KW - Hypertension
KW - Renin
KW - Sodium
KW - Sympathetic nervous system
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U2 - 10.1093/ajh/1.4.353
DO - 10.1093/ajh/1.4.353
M3 - Article
C2 - 2850819
AN - SCOPUS:0023701523
VL - 1
SP - 353
EP - 358
JO - American Journal of Hypertension
JF - American Journal of Hypertension
SN - 0895-7061
IS - 4
ER -