S. John et al., Low-density lipoprotein-cholesterol determines vascular responsiveness to angiotensin II in normocholesterolaemic humans, J HYPERTENS, 17(12), 1999, pp. 1933-1939
Citations number
37
Categorie Soggetti
Cardiovascular & Respiratory Systems","Cardiovascular & Hematology Research
Objective Both LDL-cholesterol and angiotensin II have been shown to increa
se the risk for and severity of cardiovascular disease. In hypercholesterol
aemia, experimental studies have demonstrated an increased angiotensin type
1 (AT(1)) receptor expression on vascular smooth muscle cells and an incre
ased vascular responsiveness to vasopressors has been documented in humans.
We investigated in a normocholesterolaemic young population whether vascul
ar responsiveness to angiotensin II (Ang II) infusion depends on LDL-choles
terol serum levels in the systemic and renal circulation.
Design and methods Changes in systolic and diastolic blood pressure (Delta
BP) to Ang II infusion (0.5 and 3.0 ng/kg per min) were investigated in 103
normocholesterolaemic (LDL-cholesterol < 160 mg/dl) young white men (26 +/
- 3 years; 24 h BP: 128 +/- 10/75 +/- 7 mmHg) without cardiovascular diseas
e. According to their LDL-cholesterol levels, participants were classified
into tertiles (lower tertile < 85 mg/dl, middle tertile 85-111 mg/dl, upper
tertile > 111 mg/dl).
Results Blood pressure (BP) responses to Ang II infusion 3.0 ng/kg per min
were enhanced in the group with the highest LDL-cholesterol levels (Delta s
ystolic BP: +12.8 +/- 6.7, +13.2 +/- 8.6, +17.9 +/- 9.6, P < 0.02; Delta di
astolic BP: +11.1 +/- 5.8, +11.5 +/- 6.5, +16.5 +/- 8.3, P < 0.01, for the
lower, middle and upper tertiles, respectively). This holds true when basel
ine BP was taken into account as a confounding covariable (P < 0.015), BP r
esponses to Ang II infusion were related to LDL-cholesterol serum levels (D
elta systolic BP: r = 0.26, P= 0.01; Delta diastolic BP: r = 0.32, P = 0.00
1). In multiple stepwise regression analysis, LDL-cholesterol emerged as th
e strongest determinant of vascular responsiveness to Ang II (Delta systoli
c BP: P < 0.01; Delta diastolic BP: P < 0.001).
Conclusion In young male subjects, responsiveness to Ang II is determined b
y the LDL-cholesterol serum level even in the normal range of LDL-cholester
ol, thereby potentially contributing to the cardiovascular risk of LDL-chol
esterol even within the so-called normal range. (C) Lippincott Williams & W
ilkins.