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J Ménard

Publications and source records attributed to J Ménard.

At least 55 records · Page 3Linked to original sources
PubMed1997

Vascular angiotensin-converting enzyme expression regulates local angiotensin II.

We tested the hypothesis that changes in angiotensin-converting enzyme (ACE) gene expression can regulate the rate of local vascular angiotensin II (Ang II) production. We perfused isolated rat hindlimbs with an artificial medium and infused renin and Ang I via the perfusate. Ang I and II were measured by radioimmunoassay. We then increased ACE gene expression and ACE levels in the rat aorta by producing two-kidney, one clip (2K1C) hypertension for 4 weeks. Gene expression was measured by RNAse protection assay, and ACE activity in the vessel wall was measured by the Cushman-Cheung assay. Angiotensin I infusion at 1, 10, 100, and 1000 pmol/mL led to 371 +/- 14 (+/-SEM), 3611 +/- 202, 44,828 +/- 1425, and 431,503 +/- 16,439 fmol/mL Ang II released, respectively, from the hindlimbs (r = .98, P < .001). Thus, the conversion rate did not change across four orders of magnitude, and the system was not saturable under these conditions. In 2K1C hindlimbs, Ang I infusion (0.5 pmol/mL) resulted in increased Ang II generation (157 +/- 16 versus 123 +/- 23 fmol/mL, P = .014 at minute 10) compared with controls. ACE gene expression and ACE activity were increased in 2K1C hindlimbs compared with controls (36 +/- 4 versus 17 +/- 1 mU/mg protein, P < .001). Ang II degradation in the two groups did not differ. To investigate the conversion of locally generated Ang I, we infused porcine renin (0.5 milliunits per mL) into 2K1C and control hindlimbs. Despite markedly higher Ang I release in sham-operated than in 2K1C rats (71 +/- 8 versus 37 +/- 6 pmol/mL, P = .008 at minute 12), Ang II was only moderately increased (36 +/- 3 versus 25 +/- 6 pmol/mL, P = .12 at minute 12). This difference between 2K1C rats and controls reflected a higher rate of conversion in 2K1C rats. Thus, Ang I conversion in the rat hindlimb is linear over a wide range of substrate concentrations and occurs at a fixed relationship. Nevertheless, increased ACE gene expression and ACE activity in the vessel wall lead to an increase in the conversion of Ang I to Ang II. We conclude that local ACE gene expression and ACE activity can influence the local rate of Ang II production.

Angiotensin I↗
PubMed1997

Additive effects of losartan and enalapril on blood pressure and plasma active renin.

The combination of single oral doses of an angiotensin I-converting enzyme inhibitor (captopril) and a type 1 angiotensin II receptor antagonist (losartan) has additive effects on blood pressure fall and renin release in sodium-depleted normotensive subjects. We planned the present study to determine whether the magnitude of the hemodynamic and hormonal consequences of renin-angiotensin system blockade by such a combination is larger than that obtained by doubling the dose of the angiotensin-converting enzyme inhibitor given alone. In a single-dose, double-blind, randomized, three-way crossover study, 10 mg enalapril, 20 mg enalapril, and the combination of 50 mg losartan and 10 mg enalapril were administered orally to 12 sodium-depleted normotensive subjects. The area under the time curve from 0 to 24 hours (AUC0-24) of the mean blood pressure fall after losartan-enalapril combination intake (-220 +/- 91 mm Hg.h) was significantly greater than that of either 10 or 20 mg enalapril (-124 +/- 91 and -149 +/- 85 mm Hg.h, respectively, P < .05 vs both doses). The combination significantly increased by 2.3 +/- 1.2-fold the AUC0-24 of plasma active renin compared with either 10 or 20 mg enalapril given alone (P < .05) but had no additive effect on plasma aldosterone fall. The losartan-enalapril combination is more effective in decreasing blood pressure and increasing plasma active renin than doubling of the enalapril dose.

Adolescent↗
PubMed1997

Dose effects of human renin in rats transgenic for human angiotensinogen.

We examined the effect of chronic human renin infusion and human renin inhibition on blood pressure in a unique transgenic rat model. We infused incremental doses of human renin (1 to 500 ng/h) with minipumps for 10 days into rats harboring the human angiotensinogen gene [TGR (hAOGEN)1623]. We measured blood pressure and heart rate continuously by telemetry. We found that human renin at 5 ng/h was necessary to increase blood pressure, whereas 10 ng/h caused systolic blood pressure to increase to 215 +/- 13 mm Hg. Heart rate decreased initially but then increased by 100 beats per minute compared with basal values. Drinking behavior also increased. Doses as high as 500 ng/h did not increase blood pressure further. A linear relationship was found between the log of plasma renin activity and systolic blood pressure that increased in slope from days 2 to 9. Rat angiotensinogen levels were low and not influenced by human renin infusion. Human angiotensinogen levels remained stable until 500 ng/h human renin was infused, at which time they decreased by 50% at 9 days. Rat renin gene expression (RNase protection assay) was decreased by human renin infusion, whereas rat and human angiotensinogen gene expressions in liver and kidney as well as angiotensin-converting enzyme gene expression in kidney were not affected. The human renin inhibitor Ro 42-5892 was given by gavage repeatedly to rats receiving human renin at 40 ng/h. Ro 42-5892 lowered blood pressure promptly to basal values. High human renin hypertension in this model is dose dependent, features a steeper relationship between blood pressure and plasma renin activity over time, and is associated with tachycardia and increased drinking. We conclude that the human angiotensinogen transgenic rat offers new perspectives in the study of human renin-induced hypertension.

Angiotensinogen↗
PubMed1997

High plasma level of N-acetyl-seryl-aspartyl-lysyl-proline: a new marker of chronic angiotensin-converting enzyme inhibition.

The acute administration of the angiotensin-converting enzyme (ACE) inhibitor captopril to healthy subjects transiently increases 5.5-fold the plasma levels of a natural stem-cell regulator, N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP). The aim of this study was to measure plasma Ac-SDKP levels during chronic treatment with all types of ACE inhibitors and to assess its relevance as a marker of ACE inhibition. Plasma levels of Ac-SDKP were blindly determined in age- and sex-matched hypertensive patients either treated (ACEI group, n=27) or not (non-ACEI group, n=23) with an ACE inhibitor for more than 1 month. Geometric mean [range] of plasma Ac-SDKP levels were significantly higher in the ACEI group (3.78 [1.48 to 14.5] pmol/mL) than in the non-ACEI group, with no overlap between the groups (0.75 [0.36 to 1.22] pmol/mL, P<.0001). The measurement of Ac-SDKP in plasma discriminated all the patients of the ACEI group, whereas the simultaneous determination of either in vitro (using hippuryl-histidine-leucine as substrate) or in vivo (angiotensin II/angiotensin I ratio) ACE activity failed to identify nine and five cases, respectively. We conclude that Ac-SDKP accumulates in plasma during chronic ACE inhibitor treatment. The long-term consequences of Ac-SDKP accumulation are unknown. The reliability of plasma Ac-SDKP measurement makes it the best marker of chronic ACE inhibition, which can help to verify patients' compliance to ACE inhibitor treatment.

Adolescent↗
PubMed1997

[Evaluation of the quality of filling out medical records in a hypertension consultation].

The aim of the study was to evaluate the completion of medical records of a hypertension clinic and to compare standardized computerized records versus standard medical records. The medical records of 163 consecutive hypertensive patients attending at the Broussais hospital hypertension clinic between December 1995, 6th and January 1996, 21st were checked. At the last visit, the patients were attended by 16 physicians working in 4 different teams. The medical data were recorded by physicians in the computerized system called ARTEMIS in 120 patients and in standard structured forms in 43 patients. The patients notes were checked to see if 9 clinical items were recorded at the first visit (V1), at the visit before last (V2) and at the last visit (V3). The overall completion rate was high at V1 (92.2%) and significantly decreased at follow-up visits (82.6% at V2 and 83.2% at V3). The completion rate was significantly higher in the computerized records than in the standard notes: 95.8% vs 82.2% at V1, 91.9% vs 56.3% at V2 and 91.6% vs 59.7% at V3. During follow-up (V2 vs V1), a significant decrease in the completion rate of 6 items was observed in the standard notes (tobacco use, alcohol consumption, physical activity, compliance to treatment, body weight, manual blood pressure measurement). In the computerized records, only physical activity completion rate decreased. In conclusion, the computer may help to increase the quality of the medical records as reflected by the completion rate of items related to hypertension care.

Cardiology Service, Hospital↗
PubMed1996

Vascular damage without hypertension in transgenic rats expressing prorenin exclusively in the liver.

We have developed a transgenic animal model to investigate the effects of overexpression of rat prorenin on the cardiovascular system. Two transgenic rat lines were generated in which rat prorenin expression was directed to the liver by a human alpha1-antitrypsin promoter. Liver-specific expression was confirmed by RNase protection assay. Plasma prorenin concentrations in transgenic rats were increased 400-fold in the males of both lines but were increased only two- to threefold in the females. Thus, transgene expression exhibited sexual dimorphism. Blood pressures were not significantly higher in transgenic rats than in nontransgenic controls. The ratio of heart weight to body weight was greater in male transgenic rats than in the nontransgenic controls. Histological analysis revealed severe renal lesions and hypertrophic cardiomyocytes in transgenic males only. This transgenic model demonstrates a likely role of prorenin in the development of cardiac and renal pathology independent of hypertension. These animals will facilitate studies of the effects of blockade of the renin-angiotensin system and other pharmacological interventions on the development and treatment of cardiac, vascular, and renal lesions induced by changes in this system in the absence of chronic hypertension.

Angiotensinogen↗
PubMed1996

Acute angiotensin-converting enzyme inhibition increases the plasma level of the natural stem cell regulator N-acetyl-seryl-aspartyl-lysyl-proline.

Angiotensin I-converting enzyme (ACE) has two homologous active NH2- and COOH-terminal domains and displays activity toward a broad range of substrates. The tetrapeptide N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) has been shown to be hydrolyzed in vitro by ACE and to be a preferential substrate for its NH2-terminal active site. This peptide is a regulatory factor of hematopoiesis which reversibly stem cells and normal early progenitors into S-phase. We found that a single oral dose of 50 mg of the ACE inhibitor, captopril, when administered to eight healthy subjects in a double-blind, crossover, placebo-controlled study, massively increased the plasma level of Ac-SDKP. ACE inhibition by captopril induced a 90-99% inhibition of in vitro [3H]Ac-SDKP hydrolysis and a long-lasting 5.5-fold (range: 4-8.5-fold) increase in the plasma levels of Ac-SDKP. These results demonstrate that Ac-SDKP is the first natural peptide hydrolyzed by the NH2-terminal domain of ACE not only in vitro but also in vivo, confirming that both catalytic sites of ACE are physiologically active. Our data suggest that ACE may also be implicated in the process of hematopoietic stem cell regulation, by permanently degrading this natural circulating inhibitor of cell entry into S-phase.

Administration, Oral↗
PubMed1996

[Introduction to quantitative semiology].

Clinicians regularly confront dilemmas when ordering and interpreting diagnostic tests. This paper presents the basic principles necessary for the critical appraisal of articles about diagnostic tests. Basic notions such as sensitivity and specificity are defined. The advantages of using the newer notion of likelihood ratios are underlined. Since all these quantities are estimates of unknown true values, the method for calculating confidence intervals are reported. Finally, the simplified expression of Bayes' theorem based on the use of likelihood ratios is described alongside with a simple nomogram making it possible to calculate posttest probabilities at the bedside.

Bayes Theorem↗
PubMed1996

Home self blood pressure measurement in general practice. The SMART study. Self-measurement for the Assessment of the Response to Trandolapril.

The SMART study (Self-Measurement for the Assessment of the Response to Trandolapril) was performed in general practice and enrolled 1710 patients in order to assess on a large scale the feasibility and informative value of self-measurement of blood pressure at home (SMBP), define home blood pressure (BP) levels in comparison to office readings, and determine the number of home measurements necessary to provide an accurate and precise BP value. After a 2-week washout period, patients with office diastolic blood pressure within the range 95 to 119 mm Hg received 2 mg trandolapril once daily in the morning for 4 weeks. Four days of SMBP were performed both at the end of the washout period and the end of the treatment period, with an automatic printer-equipped oscillometric device (A&D UA751). The first day values were not analyzed. Thus, the maximum number of BP measurements obtained per patient and per period was 18. Four hundred and twenty-four patients (25%) did not perform any measurements. One thousand one hundred and nine patients (65%) performed at least 4 measurements. Among them, 619 (36%) correctly performed all 18 measurements. A preference for digits 0 and 5 was detected in physicians' measurements (three consecutive values, during a single office visit). This digit preference was not found with the semiautomatic device. When the number of measurements selected for analysis was increased from 1 to 18, in the 604 patients who provided all recordings and fullfilled all protocol criteria, the standard deviation of the mean BP of the cohort was reduced by 17% for SBP and by 23% for DBP. Eighty-five percent of this reduction was already achieved by six home measurements taken at random. BP was significantly lower at home than at the office by 13 +/- 15 mm Hg for systolic BP (SBP), and 8 +/- 10 mm Hg for diastolic BP (DBP). This difference was independent of age, more marked in women (P < .001 for SBP and P < .05 for DBP), and had a Gaussian distribution. Under treatment, office SBP/DBP decreased from 166.4 +/- 14.8/101.4 +/- 5.7 mm Hg to 144.7 +/- 14.2/86.1 +/- 8.3 mm Hg, while SMBP decreased from 153.2 +/- 17.8/93.8 +/- 10.1 mm Hg to 139.4 +/- 16.4/85.1 +/- 9.5 mm Hg (all P < .0001). A major aim in research studies and individual care is to reduce BP measurements variability. This study demonstrates the ability to evaluate baseline SMBP level in two-thirds of patients previously unfamiliar with the method, the ability to evaluate treatment effect in about one-half of the patients, the improvement in the measurement precision obtained with the repetition of measures (at least six home measurements), and the absence of bias of SMBP as compared to office measurements.

Adolescent↗
PubMed1996

Integration of trial, meta-analysis and cohort results with treatment guidelines.

IMPORTANCE OF GUIDELINES: Guidelines to medical practice are of vital importance because of the fast and uncontrolled introduction of new technologies, increasing amounts of information, including contradictory results, high levels of inappropriate care and increased financial pressure. Thus guidelines can help solve common problems in all health care systems worldwide. PREPARATION OF GUIDELINES: In preparing guidelines, a synthesis of results from the literature prepared by a single expert must be compared with syntheses done by others, and a consensus recommendation may then be issued. Such a recommendation will not be based exclusively on the results of controlled trials, even when they have indisputable internal validity. There is still a need for a value judgement within a particular psychological and socio-economic context. FREEDOM FOR PHYSICIAN: It is important to preserve the physician's freedom to prescribe drugs or not in conjunction with informed choice by the patient concerning the risks of any long-term drug intervention, even if this freedom of choice does not fit with the expectations of "managed' care or third-party payers.

Clinical Trials as Topic↗
PubMed1996

Bradykinin pathway is involved in acute hemodynamic effects of enalaprilat in dogs with heart failure.

To determine the role of the renin-angiotensin system and the bradykinin pathway in the mechanism of action of angiotensin-converting enzyme inhibitors in heart failure, the acute effects of enalaprilat (1 mg/kg) were compared with those of a renin inhibitor (ciprokiren, 1 mg/kg i.v.) in 10 chronically instrumented conscious dogs with heart failure induced by right ventricular pacing (3 wk, 240 beats/min). The effects of enalaprilat and ciprokiren on bradykinin infusion (3, 10, and 30 micrograms/min) and the effects of enalaprilat in the presence of the bradykinin B2 receptor antagonist Hoe-140 (10 micrograms/kg i.v.) were also examined. Both inhibitors significantly decreased mean aortic pressure and increased cardiac output. However, enalaprilat induced significantly greater hemodynamic effects than ciprokiren (mean aortic pressure, -13 +/- 3 vs. -6 +/- 1 mmHg; cardiac output, 0.4 +/- 0.1 vs. 0.15 +/- 0.1 l/min). Bradykinin infusion led to dose-dependent decreases in mean aortic pressure and increases in cardiac output that were not modified by pretreatment with ciprokiren but were potentiated 10-fold by enalaprilat. Hoe-140 significantly reduced the hemodynamic effects of enalaprilat. Thus endogenous bradykinin is involved in the acute hemodynamic effects of enalaprilat in experimental heart failure.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1996

Human renin-dependent hypertension in rats transgenic for human angiotensinogen.

To examine the utility of rats transgenic for human angiotensinogen in the study of human renin-induced hypertension, we first developed assays to measure both the human and rat renin-angiotensin systems in these rats. We used human and mouse renin, transgenic human angiotensinogen, and the human renin inhibitor Ro 42-5892 to determine human- and rat-specific plasma angiotensinogen concentrations, renin activity, and renin concentration. The assays were validated with rat and human plasma mixed in known amounts and with plasma from rats transgenic for human renin. We then tested the human angiotensinogen-transgenic rats by infusing recombinant human renin over 10 days (50 ng/h, n=4) with osmotic minipumps. High human angiotensinogen transgene expression was found in the liver, brain, kidney, gastrointestinal tract, and aorta, whereas rat angiotensinogen gene expression was detected in the liver and brain. During human renin infusion, blood pressure increased to >200/150 mm Hg. Before infusion, human angiotensinogen was 100-fold greater than rat angiotensinogen (141 +/- 73 versus 1.2 +/- 0.16 microg angiotensin l/mL); the relation was not changed by renin infusion. Plasma renin activity increased 300-fold; human plasma renin concentration increased to very high levels (449 +/- 262 ng of angiotensin I per mL per hour), whereas rat plasma renin concentration decreased to undetectable levels. Thus, chronic human renin infusion resulted in severe hypertension with extreme plasma renin activity and plasma renin concentration. However, even at these levels, human angiotensinogen was not rate limiting and angiotensin II was not a significant stimulus for angiotensinogen production. We conclude that these transgenic rats represent a novel model of human renin-dependent hypertension.

Angiotensinogen↗
PubMed1996

Assessment of drug efficacy using home self-blood pressure measurement: the SMART study. Self Measurement for the Assessment of the Response to Trandolapril.

UNLABELLED: The SMART study (Self Measurement for the Assessment of the Response to Trandolapril) was a large scale trial conducted by general practitioners in order to assess the informative value of home self-measured blood pressure (BP) for the evaluation of therapeutic intervention. After a 2-week wash-out period, patients with office diastolic blood pressure (DBP) between 95 and 120 mm Hg received trandolapril, 2 mg once daily for 4 weeks. Four days of self-recorded BP were performed both at the end of the wash-out period and at the end of the treatment period with an automatic printerequipped device using the oscillometric method (A&D UA 751). Every day, a series of three consecutive measurements was planned in the morning before drug intake and repeated in the evening. A total of 1710 patients (946 men, 764 women) aged 56 +/- 11 entered the study. In the 816 patients who correctly performed self-measured blood pressure (SMBP) during both periods and followed the protocol schedule, office BP (SBP/DBP) decreased from 166.4 +/- 15/101.4 +/- 6 mm Hg to 144.7 +/- 14/86.1 +/- 8 mm Hg while SMBP decreased from 153 +/- 18/94 +/- 10 mm Hg to 139 +/- 16/85 +/- 10 mm Hg. A weak correlation was found between the two methods with regard to systolic (r = 0.47, P < 0.0001) and diastolic (r = 0.36, P < 0.0001) BP lowering. Individual response to therapy varied between the two methods: 633 patients (77.6%) exhibited at least a 10 mm Hg office DBP decrease while 493 (60.4%) presented at least a 6 mm Hg self measured DBP decrease in the evening; 65% of patients were considered as responders with both methods. The 24-h therapeutic coverage was assessed by the morning to evening BP decrease ratio (M/E ratio) which represents the ratio of the trough effect to the 12-h post dosing efficacy. Both population and individual M/E ratios ranged between 73% and 86% thus confirming the long duration of action of trandolapril. IN CONCLUSION: (1) discrepancies between office and self-measured BP evaluation of therapeutic response have been pointed out: agreement between the two methods is obtained in only 65% of patients, mainly due to intra-individual BP variability and recording conditions; and (2) self-measured BP could be a potential tool to explore the 24-h therapeutic coverage.

Adolescent↗
PubMed1996

[Development of a model of human renin hypertension in rats].

The effective development of human renin inhibitors meets its major obstacle in the absence of a suitable experimental rodent model and the species-specificity of human renin, exclusively cleaving its natural substrate human angiotensinogen. We have reconstructed the human renin-angiotensin system in transgenic rats over expressing the human angiotensinogen gene TGR (hAOGEN) 1623 by chronically injecting i.v. human recombinant renin. We have first established new in vitro enzyme kinetic techniques to measure the various components of the chimeric renin-angiotensin system and distinguished the two human and rat-specific pathways of generating angiotensin I by the human specific renin inhibitor Ro 42-5892 (Hoffmann-La Roche). Male heterozygous TGR had plasma levels of rat angiotensinogen of 1.2 +/- 0.2 mg Ang l/ml while the plasma levels of the transgene were 141 +/- 98 mg Ang l/ml (n = 41; not normally distributed). Transgene expression was found in the liver kidney, aorta, heart and adrenals. Four rats were infused i.v. with human recombinant renin at 50 ng/h over 9 days which chronically increased their blood pressure to > 200 mmHg while total plasma renin activity increased by a factor of 300. Rat renin disappeared form the plasma. This new model of experimental human renin-induced hypertension in rats will facilitate the screening and characterization of human renin inhibitors.

Angiotensinogen↗
PubMed1996

[Short and long-term clinical tolerance of hypertensive treatment during the HOT study (Hypertension Optimal Treatment)].

International, prospective, randomized HOT study aims to determine the optimal BP level under treatment in order to reduce at the most the cardiovascular morbidity/mortality. Defined by randomization, the level to obtain is DBP < or = 80, 85, 90 mmHg. The treatment is started by felodipine 5 mg/day then, if necessary, a bitherapy is prescribed and then, if necessary, a tritherapy. 19,193 patients have been included (BP at randomization 170 +/- 15/105 +/- 4 mmHg). After 1 year treatment, it is possible to search for the influence on the clinical tolerance of sex, age, BP goal, geographic area, time and treatment. The percentage of patients with side effects by BP goals and by treatment type are, during the time and in different geographic areas, the following (NE/Northern Europe = Norway, Switzerland, Belgium, Hungary, Sweden, Denmark, Finland, The Netherlands, UK, Germany, Austria; SE/Southern Europe = Italy, Spain, Greece): [table: see text] The target BP and age don't nearly influence the clinical tolerance. The side effects reported by the physicians are more numerous at the treatment start than at longeur terme. That is due to the therapeutic modifications of the physicians or to a better acceptation of the drugs by the patients or to a real disappearance of the side effects. Reported side effects are more frequent in Southern Europe, France than Northern Europe and more frequent among women that men. The incidence of side effects is proportional to the number of prescribed drugs. Time and the number of antihypertensive drugs appear as the most important factors.

Age Factors↗
PubMed1995

Additive effects of combined angiotensin-converting enzyme inhibition and angiotensin II antagonism on blood pressure and renin release in sodium-depleted normotensives.

BACKGROUND: Angiotensin-converting enzyme (ACE) inhibitors do not decrease plasma angiotensin (Ang) II levels 24 hours after drug intake to the same extent as at peak. This intermittent partial "escape" is explained either by a renin-mediated reactive rise in plasma Ang I or by non-ACE-dependent Ang II generation. We therefore tested the hypothesis that a combination of ACE inhibition and Ang II blockade may have additive biological and hemodynamic effects. METHODS AND RESULTS: In a single-dose, double-blind, randomized, four-way, crossover study, an Ang II antagonist (losartan 50 mg), an ACE inhibitor (captopril 50 mg), their combination, and matched placebos were orally administered to 12 normotensive male volunteers maintained in mild sodium depletion. When captopril 50 mg and losartan 50 mg were given alone, the magnitude of their effects on blood pressure, plasma active renin, Ang I, and aldosterone was similar, whereas the kinetics of their effects were different, reflecting differences in drug pharmacokinetics. The losartan-captopril combination completely suppressed the rise in plasma Ang II induced by losartan 2 hours after drug intake (3.3 +/- 3.6 pg/mL versus 20.3 +/- 19.1 pg/mL, respectively, P < .05). Six hours after drug intake, the losartan-captopril combination induced a significantly greater decrease in mean blood pressure than that produced by either losartan or captopril alone (73 +/- 7 mm Hg versus 79 +/- 8 mm Hg versus 81 +/- 7 mm Hg, respectively, P < .05). The maximum placebo-subtracted falls in mean blood pressure for the losartan-captopril combination, captopril 50 mg, and losartan 50 mg were 14 +/- 5 mm Hg, 10 +/- 3 mm Hg, and 9 +/- 6 mm Hg, respectively (F2.22 = 3.45, P < .05). The duration of the mean blood pressure fall was not prolonged by the combination. After combined losartan-captopril administration, the area under the plasma active renin versus time curve (0 to 24 hours) was significantly increased when compared with either losartan or captopril alone (6404 +/- 2961 pg.h.mL-1 versus 3105 +/- 1461 pg.h.mL-1 versus 2092 +/- 867 pg.h.mL-1, respectively, P < .05). The combination had no additive effects on plasma aldosterone decrease when compared with either losartan or captopril alone (58 +/- 17% versus 51 +/- 20% versus 53 +/- 21%, respectively, NS). CONCLUSIONS: The combined administration of a standard single oral dose of an ACE inhibitor and an Ang II antagonist to mildly sodium-depleted normal subjects (1) had a major additive effect on plasma renin rise, (2) induced an additional mean blood pressure reduction, and (3) had no additive effect on plasma aldosterone fall.

Adolescent↗