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Nitric oxide and malondialdehyde levels in healhty normotensive subjects and hypertensive patients
AJH–May 2004 –VOL. 17, NO. 5, PART 2
POSTERS: Endothelial Factors (endothelin, nitric oxide, etc.)
P-106 NITRIC OXIDE AND MALONDIALDEHYDE LEVELS IN HEALHTY NORMOTENSIVE SUBJECTS AND HYPERTENSIVE PATIENTS Rafael Hernandez-Hernandez, Maria C Armas-Padilla, Rosalba Cammarata, Beatriz Sosa-Canache, Betriz Pacheco, Jaime Guerrero, Atiff R Carvajal, Maria J Armas-Hernandez. Clinical Pharmacology Unit, Hypertension Clinic, School of Medicine, Universidad Centroccidental Lisandro Alvarado, Barquisimeto, Lara, Venezuela.
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significantly intracellular Mg⫹⫹ (32.2⫾1.3 vs 34.8⫾1.4 mEq/l; p⫽0.001). The SPECT-scan derived ischemia-index showed no significant changes following active or P treatment as compared to baseline (baseline: 7.78⫾6.94; P: 7.04⫾6.64; Mg⫹⫹: 8.3⫾7.23, NS). Mg⫹⫹ did not influence endothelium dependent or independent vasodilatation (figure) as well as the quality of life score. Patients presenting with S-X did not benefit from orally applied Mg⫹⫹ treatment. The present results might be explained by a lack of magnesium deficiency in the study population at baseline or by more severe endothelial dysfunction in S-X pts as well.
With the aim of evaluating serum and urinary nitric oxide (NO) levels and serum malondialdehyde (MDA) levels in healthy normotensive subjects and patients with essential hypertension a group of twenty one healthy normotensive subjects (age: 39.24 ⫾ 1.81 years, 8 males 13 females, BMI: 27.9) and forty two patients with untreated essential hypertension (age: 47.62 ⫾ 1.72 years, 19 males 23 females, BMI: 28.3) were studied. Determination of serum and 24-hour urinary NO (Griess Reagent) and serum MDA (Valle-Santos method) levels were performed in a blind fashion. Normotensives** Hypertensives** p values*** SBP (mmHg)* 121.3 ⫹/⫺ 2.5 DBP (mmHg)* 78.4 ⫹/⫺ 1.3 MAP (mmHg)* 92.7 ⫹/⫺ 1.6 57.33 ⫹/⫺ 6.5 Serum NO (M/L) 131.32 ⫹/⫺ 27.7 Urinary NO (M/L) Renal Clearance NO (ml/min) 0.66 ⫹/⫺ 0.11 MDA (nM) 1.21 ⫹/⫺ 0.05
166.4 ⫹/⫺ 4.3 ⬍0.001 102.9 ⫹/⫺ 1.83 ⬍0.001 124.1 ⫹/⫺ 2.5 ⬍0.001 35.13 ⫹/⫺ 3.4 0.0041 63.83 ⫹/⫺ 5.5 0.0255 1.52 ⫹/⫺ 0.22 0.0002 1.36 ⫹/⫺ 0.05 0.0435
* Office blood pressure, supine position. ** Mean ⫹/⫺ Standard Error. *** Unpaired Student t-test
Results are shown as follows: In conclusion patients with essential hypertension, in comparison to normotensive subjects, showed reduction in serum and urinary NO levels with elevation of NO renal clearance and increment of MDA serum levels indicating endothelial dysfunction with high lipid peroxidation state. The acceleration of the atherogenic process and the higher incidence of cardiovascular outcomes observed in hypertensive patients could, in part, be explicated by this difference. Key Words: Nitric Oxide, Malondialdehyde, Lipid Peroxidation
P-107 EFFECTS OF ORAL MAGNESIUM (MGⴙⴙ) AND POTASSIUM (Kⴙ) THERAPY ON THALLIUM PERFUSION SCAN DEFECTS, QUALITY OF LIFE AND PULSE WAVE ANALYSIS IN HYPERTENSIVE PATIENTS WITH SYNDROME X Sabine Hoerzer, Thomas C Wascher, Rainer W Lipp, Josef Haas, Werner W Klein, Robert Zweiker. Dept of Internal Medicine, K.-F. University Graz, Graz, Styria, Austria. Previous studies have shown that Mg⫹⫹/K⫹ supplementation improves symptoms and endothelial function in patients (pts) with coronary artery disease (CAD). The aim of the present study was to investigate these effects in pts with syndrome X (S-X). Twenty-seven S-X pts with hypertension (16 men, 11 women, mean⫾SD age 62⫾8, range 48 –77 years) were included in this double-blinded placebo (P) controlled study. S-X was defined as the presence of chest pain and signs of myocardial ischemia in thallium SPECT-scan in absence of significant CAD (⬍30% lumen narrowing defined by coronary angiography). Mg⫹⫹ (30mmol) once daily or P were orally given to all pts. Primary endpoint was defined as an index of ischemia. It was computed by the number of ischemic myocardial segments recorded by a Tl-201-SPECT-scan after a treadmill stress test. Secondary endpoints were quality of life (QLQ-C30), stiffness and reflection (RI) indices derived from pulse wave analysis. RI changes were used for determination of endothelium-dependent and independent vasodilatation. All investigations were done three-times in all pts(baseline and following P and Mg⫹⫹ therapy). Mg⫹⫹-therapy increased
Key Words: Syndrome X, Pulse Wave Analysis, Magnesium
P-108 ENDOTHELIAL FUNCTION IN PATIENTS WITH SLEEP APNEA BUT WITHOUT HYPERTENSION Huseyin Oflaz, Caglar Cuhadaroglu, Burak Pamukcu, Ahmet K Bilge, Turhan Ece, Nevres Koylan. Cardiology, Istanbul Faculty of Medicine, Istanbul, Turkey; Chest Disease, Istanbul Faculty of Medicine, Istanbul, Turkey. Hypertension is very frequent in patients with sleep apnea (SA). To evaluate the role of endothelial dysfunction in the pathogenesis of hypertension in patients with SA, 23 patients with SA but without hypertension (20 men and 3 women, mean age 47.8 ⫾ 7.8 years) and 15 healthy normotensive subjects (11 men and 4 women, mean age 46.2 ⫾ 7.8 years) were investigated. The presence or absence of SA was evaluated with minimal oxygen saturations and apnea/hypopnea indexes during sleep study in all patients and control subjects. All other baseline characteristics including blood pressure, body weight and cholesterol levels were equivalent between two groups. None of the study subjects were using ACE inhibitors, angiotensin II receptor blockers, calcium channel blockers or statins. Three SA patients and three subjects from the control group were smokers. Ultrasound assessment of brachial artery flow-mediated dilation during reactive hyperemia (FMD) and nitroglycerine induced dilation (NID) of the same vessel were used as a noninvasive and broadly applicable methods for the examination of endothelial function. Baseline vessel diameters were similar in both groups. Vessel diameter during FMD was significantly lower in patients with SA (6.05 ⫾ 3.18 mm vs 10.99 ⫾ 2.66 mm; p⬍0.0001). On the other hand, vessel diameters during NID were similar in both SA patients and the control subjects (12.96 ⫾ 6.6 vs 14.4 ⫾ 4.07 mm). Percent increases of vessel diameters during FMD were also significantly low in patients with SA when compared with the control group (89.14 ⫾ 47.4 % vs. 165.51 ⫾ 52.35 %, p⬍ 0.0001); while the comparison of percent increases at vessel diameters during NID at both groups was insignificant. These findings confirm the presence of endothelial dysfunction demonstrated by the decrease of endothelium mediated vasodilation despite normal vasodilatory response to nitroglycerine in patients with SA but without hypertension. This fact may be one of the possible mechanisms for the development of hypertension in patients with SA. Key Words: Sleep Apnea, Endothelial Function, Flow Mediated Dilation
POSTERS: Endothelial Factors (endothelin, nitric oxide, etc.)
P-106 NITRIC OXIDE AND MALONDIALDEHYDE LEVELS IN HEALHTY NORMOTENSIVE SUBJECTS AND HYPERTENSIVE PATIENTS Rafael Hernandez-Hernandez, Maria C Armas-Padilla, Rosalba Cammarata, Beatriz Sosa-Canache, Betriz Pacheco, Jaime Guerrero, Atiff R Carvajal, Maria J Armas-Hernandez. Clinical Pharmacology Unit, Hypertension Clinic, School of Medicine, Universidad Centroccidental Lisandro Alvarado, Barquisimeto, Lara, Venezuela.
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significantly intracellular Mg⫹⫹ (32.2⫾1.3 vs 34.8⫾1.4 mEq/l; p⫽0.001). The SPECT-scan derived ischemia-index showed no significant changes following active or P treatment as compared to baseline (baseline: 7.78⫾6.94; P: 7.04⫾6.64; Mg⫹⫹: 8.3⫾7.23, NS). Mg⫹⫹ did not influence endothelium dependent or independent vasodilatation (figure) as well as the quality of life score. Patients presenting with S-X did not benefit from orally applied Mg⫹⫹ treatment. The present results might be explained by a lack of magnesium deficiency in the study population at baseline or by more severe endothelial dysfunction in S-X pts as well.
With the aim of evaluating serum and urinary nitric oxide (NO) levels and serum malondialdehyde (MDA) levels in healthy normotensive subjects and patients with essential hypertension a group of twenty one healthy normotensive subjects (age: 39.24 ⫾ 1.81 years, 8 males 13 females, BMI: 27.9) and forty two patients with untreated essential hypertension (age: 47.62 ⫾ 1.72 years, 19 males 23 females, BMI: 28.3) were studied. Determination of serum and 24-hour urinary NO (Griess Reagent) and serum MDA (Valle-Santos method) levels were performed in a blind fashion. Normotensives** Hypertensives** p values*** SBP (mmHg)* 121.3 ⫹/⫺ 2.5 DBP (mmHg)* 78.4 ⫹/⫺ 1.3 MAP (mmHg)* 92.7 ⫹/⫺ 1.6 57.33 ⫹/⫺ 6.5 Serum NO (M/L) 131.32 ⫹/⫺ 27.7 Urinary NO (M/L) Renal Clearance NO (ml/min) 0.66 ⫹/⫺ 0.11 MDA (nM) 1.21 ⫹/⫺ 0.05
166.4 ⫹/⫺ 4.3 ⬍0.001 102.9 ⫹/⫺ 1.83 ⬍0.001 124.1 ⫹/⫺ 2.5 ⬍0.001 35.13 ⫹/⫺ 3.4 0.0041 63.83 ⫹/⫺ 5.5 0.0255 1.52 ⫹/⫺ 0.22 0.0002 1.36 ⫹/⫺ 0.05 0.0435
* Office blood pressure, supine position. ** Mean ⫹/⫺ Standard Error. *** Unpaired Student t-test
Results are shown as follows: In conclusion patients with essential hypertension, in comparison to normotensive subjects, showed reduction in serum and urinary NO levels with elevation of NO renal clearance and increment of MDA serum levels indicating endothelial dysfunction with high lipid peroxidation state. The acceleration of the atherogenic process and the higher incidence of cardiovascular outcomes observed in hypertensive patients could, in part, be explicated by this difference. Key Words: Nitric Oxide, Malondialdehyde, Lipid Peroxidation
P-107 EFFECTS OF ORAL MAGNESIUM (MGⴙⴙ) AND POTASSIUM (Kⴙ) THERAPY ON THALLIUM PERFUSION SCAN DEFECTS, QUALITY OF LIFE AND PULSE WAVE ANALYSIS IN HYPERTENSIVE PATIENTS WITH SYNDROME X Sabine Hoerzer, Thomas C Wascher, Rainer W Lipp, Josef Haas, Werner W Klein, Robert Zweiker. Dept of Internal Medicine, K.-F. University Graz, Graz, Styria, Austria. Previous studies have shown that Mg⫹⫹/K⫹ supplementation improves symptoms and endothelial function in patients (pts) with coronary artery disease (CAD). The aim of the present study was to investigate these effects in pts with syndrome X (S-X). Twenty-seven S-X pts with hypertension (16 men, 11 women, mean⫾SD age 62⫾8, range 48 –77 years) were included in this double-blinded placebo (P) controlled study. S-X was defined as the presence of chest pain and signs of myocardial ischemia in thallium SPECT-scan in absence of significant CAD (⬍30% lumen narrowing defined by coronary angiography). Mg⫹⫹ (30mmol) once daily or P were orally given to all pts. Primary endpoint was defined as an index of ischemia. It was computed by the number of ischemic myocardial segments recorded by a Tl-201-SPECT-scan after a treadmill stress test. Secondary endpoints were quality of life (QLQ-C30), stiffness and reflection (RI) indices derived from pulse wave analysis. RI changes were used for determination of endothelium-dependent and independent vasodilatation. All investigations were done three-times in all pts(baseline and following P and Mg⫹⫹ therapy). Mg⫹⫹-therapy increased
Key Words: Syndrome X, Pulse Wave Analysis, Magnesium
P-108 ENDOTHELIAL FUNCTION IN PATIENTS WITH SLEEP APNEA BUT WITHOUT HYPERTENSION Huseyin Oflaz, Caglar Cuhadaroglu, Burak Pamukcu, Ahmet K Bilge, Turhan Ece, Nevres Koylan. Cardiology, Istanbul Faculty of Medicine, Istanbul, Turkey; Chest Disease, Istanbul Faculty of Medicine, Istanbul, Turkey. Hypertension is very frequent in patients with sleep apnea (SA). To evaluate the role of endothelial dysfunction in the pathogenesis of hypertension in patients with SA, 23 patients with SA but without hypertension (20 men and 3 women, mean age 47.8 ⫾ 7.8 years) and 15 healthy normotensive subjects (11 men and 4 women, mean age 46.2 ⫾ 7.8 years) were investigated. The presence or absence of SA was evaluated with minimal oxygen saturations and apnea/hypopnea indexes during sleep study in all patients and control subjects. All other baseline characteristics including blood pressure, body weight and cholesterol levels were equivalent between two groups. None of the study subjects were using ACE inhibitors, angiotensin II receptor blockers, calcium channel blockers or statins. Three SA patients and three subjects from the control group were smokers. Ultrasound assessment of brachial artery flow-mediated dilation during reactive hyperemia (FMD) and nitroglycerine induced dilation (NID) of the same vessel were used as a noninvasive and broadly applicable methods for the examination of endothelial function. Baseline vessel diameters were similar in both groups. Vessel diameter during FMD was significantly lower in patients with SA (6.05 ⫾ 3.18 mm vs 10.99 ⫾ 2.66 mm; p⬍0.0001). On the other hand, vessel diameters during NID were similar in both SA patients and the control subjects (12.96 ⫾ 6.6 vs 14.4 ⫾ 4.07 mm). Percent increases of vessel diameters during FMD were also significantly low in patients with SA when compared with the control group (89.14 ⫾ 47.4 % vs. 165.51 ⫾ 52.35 %, p⬍ 0.0001); while the comparison of percent increases at vessel diameters during NID at both groups was insignificant. These findings confirm the presence of endothelial dysfunction demonstrated by the decrease of endothelium mediated vasodilation despite normal vasodilatory response to nitroglycerine in patients with SA but without hypertension. This fact may be one of the possible mechanisms for the development of hypertension in patients with SA. Key Words: Sleep Apnea, Endothelial Function, Flow Mediated Dilation