Biomedical subjects

P Sassano

Publications and source records attributed to P Sassano.

At least 19 recordsLinked to original sources

PubMed1992

[Methodological problems of prevention/regression trials of atherosclerosis].

Animal models of atherosclerosis have improved our understanding of the pathogenic mechanisms involved in the formation of the atherosclerotic plaque. However, extrapolation of these data to the clinical situation is difficult. In addition, evaluation of the prevention or regression of atherosclerosis raises methodological problems. Although improved techniques provide a better evaluation of the extension of the plaques and their functional consequences, a number of points remain undecided: when to intervene, in which patients and how to extrapolate the results. A standardisation of the methods of evaluation of the atherosclerotic plaque is essential as is the fact that the benefit observed should be a reduction in cardiovascular complications and not simply the progression or regression of an angiographic lesion.

Animals↗

PubMed1991

[Validation of Oscillomat, a device for self-measurement of blood pressure. Comparison with mercury sphygmomanometers].

Self-measurement of arterial blood pressure (BP) is a valuable aid in the follow-up of hypertensive patients. Unfortunately, the devices utilized are not subject to certification and therefore must be validated. In this study, the accuracy and precision of BP measurement with the Oscillomat device were measured and simultaneously compared with those of a standard mercury sphygomomanometer in 60 subjects and with a random zero mercury sphygmomanometer in 44 subjects. The Oscillomat device correctly explored systolic and diastolic BP within a 55 to 210 mmHg range. Compared with the auscultatory method, it tended to underestimate systolic BP values by + 3 to -15 mmHg and diastolic B.P. values by + 1 to -15 mmHg.

Adult↗

PubMed1991

[Efficacy and tolerance of LA 50 mg nicardipine in hypertensive athletes].

The beneficial effects of physical exercise on the blood pressure are widely recognised. Nevertheless, some athletes remain hypertensive and the treatment of this population makes special demands with respect to treatment efficacy and tolerability, the respect of athletic performance and problems of proscribed substances. For example, the Athletic Boards have prohibited betablockers and diuretics in competitive athletes. The aim of this study was to assess nicardipine LA 50 mg administered twice daily in the special context of hypertensive athletes. Thirty-eight athletes with mild or moderate hypertension undergoing endurance training were included in this double blind trial versus placebo. After two months treatment, the systolic and diastolic blood pressures were significantly lower at rest in the nicardipine than in the placebo group (delta SBP = -18.9 vs -4.1 mmHg, p less than 0.001; delta DBP = -15.7 vs -4.1 mmHg, p less than 0.01). In addition the maximum SBP on effort was significantly lower in the nicardipine group (200 vs 215 mmHg, p less than 0.05). On the other hand, no difference was observed between the two groups as regards the maximum oxygen consumption (delta VO2 max = 6.2 vs -0.4 ml/min/kg, NS) and duration of effort (13.75 vs 12.32 min, NS), showing that athletic performance was unchanged in the group treated by nicardipine LA. These results suggest that treatment with nicardipine LA fulfills the special criteria of hypertensive athletes.

Adult↗

PubMed1991

[Use of intravenous nicardipine for the diagnosis of renovascular hypertension].

UNLABELLED: The diagnosis of remediable renovascular hypertension (RVH) requires demonstration of lateralization of renal vein renin (RVR). In order to increase the accuracy of RVR ratio, we investigated the acute effects of a bolus of Nicardipine (Nic.: 4 mg i.v.) on hemodynamics and RVR in 19 patients. 13 patients had an unilateral renal artery stenosis greater than 75% (RVH: 10 atheroma and 3 fibrodysplasia) and 6 patients had essential hypertension (EH). In 6 patients (5 RVH and 1 EH) treatment could not be discontinued and only a monotherapy by central alpha-agonists was prescribed. RVR samples were obtained 15 minutes after renal vein catheterization (baseline values: T0) and 10 minutes after Nic. injection (T10). During the whole procedure, mean blood pressure (MBP) and heart rate (HR) were monitored every 2 minutes by an automatic device. Active renin was measured by a new immunoradiometric assay. A RVR ratio (stenotic/contralateral side) greater than 1.5 was considered as a positive ischemic index. RESULTS: The relative changes in MBP and HR between T0 and T10 were of same magnitude in both groups. No patient suffered any untoward effect from the fall in MBP. Nic. increased RVR release from both sides in RVH group as well as in the EH group. At baseline, 6/13 of the RVH patients and none of the EH patients had a RVR greater than 1.5. After Nic. injection, all the RVH patients had a RVR greater than 1.5 and none among EH patients. We conclude that single i.v. Nic. bolus is a safe and a reliable procedure which increases diagnostic accuracy by enhancing RVR when there is an unilateral RVH disease.

Adult↗

PubMed1990

Parathyroid hormone and cardiovascular effects of dihydropyridines in chronic renal failure.

We studied the influence of parathyroid gland activity on cardiovascular response to dihydropyridines (nicardipine (NIC), 80 mg/day for 4 weeks) in 20 hypertensive patients with end-stage renal failure (ESRF). Before the treatment hyperparathyroidism (HPTH) was estimated on the basis of serum parathormone (PTH), and bone histomorphometry (osteoclastic resorption surfaces (ORS), and number of osteoclasts (NO]. NIC induced a significant decrease in systolic (SAP) and diastolic (DAP) arterial blood pressure, but did not significantly change the heart rate (HR) or the SAP X HR (myocardial oxygen consumption estimate). Changes in SAP and DAP were correlated to baseline serum PTH (P less than .001), to ORS (P less than .01) and to NO (P less than .01). Furthermore, a significant decrease in blood pressure was observed only in patients with histological signs of hyperparathyroidism (ORS greater than 1%). In this subset of patients NIC induced a significant decrease in SAP X HR (P less than .02) which was correlated to PTH and histomorphometric indexes of HPTH (P less than .01). The results of the present study show that blood pressure response to dihydropyridines in ESRF is associated with parathyroid activity as judged from serum PTH and bone histomorphometry.

Adult↗

PubMed1989

Crossover design for the dose determination of an angiotensin converting enzyme inhibitor in hypertension.

In order to determine the dose regimen of new antihypertensive compounds, between-patient trials are usually performed. However, the combined use of a crossover design and a precise methodology to measure blood pressure (BP) and biological effects can provide relevant data with a minimal number of patients, if there is no carryover effect which invalidates the experiment. Such goals were successfully achieved with just 25 hypertensive patients who were randomly allocated in double-blind fashion every 2 weeks to a new angiotensin converting enzyme (ACE) inhibitor, benazepril [10 mg once a day (o.d.), 20 mg o.d., 10 mg twice a day (b.i.d.) and 20 mg b.i.d.], or a placebo. The mean BP fall [systolic (SBP)/diastolic (DBP), measured in mmHg] just before drug intake was significantly greater with benazepril: -14/-9 (10 mg o.d.); -15/-8.5 (20 mg o.d.); -22.5/-14 (10 mg b.i.d.), and -21/-13 (20 mg b.i.d.) in comparison with placebo (-3/-3). Mean active plasma renin (measured in pg/ml), assessed by an immunoradiometric assay based on two monoclonal antibodies, increased significantly in a dose-dependent manner, by +0.7 (placebo), +15.0 (10 mg o.d.), +23.4 (20 mg o.d.), +44.4 (10 mg b.i.d.) and +78.8 (20 mg b.i.d.), whereas plasma ACE decreased (by 67 and 78% after 10 and 20 mg o.d., respectively, and by 91-92% after 10 and 20 mg b.i.d.). In the clinical development of an antihypertensive drug, the earlier use of such within-patient studies, with the random insertion of one placebo period between the active periods, should help in the dose-response curve search.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1989

Comparison of increase in the enalapril dose and addition of hydrochlorothiazide as second-step treatment of hypertensive patients not controlled by enalapril alone.

Forty-six patients were randomly allocated to two different groups of treatment if their diastolic blood pressure remained above 90 mm Hg after one month of treatment with 20 mg enalapril mg once daily. In the first group (ENA), 23 patients were given higher daily dosages of enalapril (40 mg and, when necessary, 60 mg). The second group of 23 patients (HCTZ) was given 20 mg/day enalapril and hydrochlorothiazide (25 mg/day and, when necessary, 50 mg). Blood pressure was measured by an automatic device and by the physician with a standard sphygmomanometer. Blood pressure was significantly lower in the HCTZ group, according to both the automatic device (130 +/- 9/80 +/- 8 vs. 141 +/- 5/86 +/- 8 mm Hg, p less than 0.01/p less than 0.05) and the sphygmomanometer (134 +/- 10/89 +/- 6 vs. 149 +/- 16/94 +/- 5 mm Hg, p less than 0.001/p less than 0.01). Plasma renin activity, increased by enalapril at the 20 mg dosage, rose in the HCTZ group but not in the ENA group (22.4 +/- 22 vs. 10.2 +/- 11 pmol/ml/h, p less than 0.05). Plasma aldosterone increased significantly in the HCTZ group (0.44 +/- 0.22 vs. 0.30 +/- 0.17 pmol/ml, p less than 0.05) but did not change in the ENA group (0.31 +/- 0.11 vs. 0.30 +/- 0.17 pmol/ml, NS). In the ENA group, converting enzyme activity was not reinforced (5.7 +/- 8 vs. 6.6 +/- 6 mU/ml, NS) despite an increase in plasma enalaprilat levels (172.4 +/- 108 vs. 72.1 +/- 42 ng/ml, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Angiotensinogen↗

PubMed1988

Plasma concentrations of atrial natriuretic peptide in patients with artificial and transplanted hearts.

Plasma atrial natriuretic peptide (ANP) concentrations were measured by radioimmunoassay 1 to 12 days after operation in six patients with artificial hearts. The mean levels were significantly higher in artificial heart recipients (58.2 pg.ml-1) than in controls (12.6 pg.ml-1). The mechanism underlying the raised values is not clear, although it is suggested that elevated atrial pressure may have been the stimulus for higher ANP release. In 3 patients plasma ANP concentrations were also measured 1 to 5 days after orthotopic transplantation. In all of them ANP concentrations had increased by 20 to 74% despite lower right atrial pressure. An increase in atrial tissue mass may have contributed to the raised plasma ANP after orthotopic transplantation. It also suggests that the functioning sympathetic nervous system is not a necessary condition for ANP release.

Adult↗

PubMed1988

[Acute response to calcium inhibitors in secondary arterial hypertension: does renin play a role?].

Calcium channel blocking agents are considered to be particularly effective in reducing blood pressure (BP) in low renin essential hypertension and in primary aldosteronism. The aim of this study was to compare the acute BP response to nicardipine in 2 opposite situations of stimulation of the renin angiotensin system: eight patients (49 +/- 13 years, mean arterial BP (MAP) 123 +/- 8 mmHg) with primary aldosteronism (active renin less than 5 pg/ml, group 1) and nine patients (38 +/- 17 years, MAP: 107 +/- 13 mmHg) with renovascular hypertension and high level of active renin (greater than 25 pg/ml, group 2). They had not taken any antihypertensive treatment since at least one week. After 60 minutes in the supine position (T0) nicardipine was infused at a rate of 7.5 mg/h during 10 minutes (T10), 15 mg/h from the 10th to 20th minute (T20) and 30 mg/h during the last ten minutes (T30). Thus, a total cumulative dose of 8.75 mg was administrated in 30 minutes. BP was recorded by an indirect oscillometric method (Sentrom) every 2 minutes and renin was assayed through an immuno-radiometric procedure (IRMA). There was an important and similar BP fall in the 2 groups (Gr 1: T10-6 p. 100, T20-17 p. 100, T30-25 p. 100; Gr 2: T10-7 p. 100, T20-13 p. 100, T30-18 p. 100) with a very significant dose-effect relation (r = 0.67, p less than 0.001). There was also an important increase in heart rate similar in the 2 groups (+35 p. 100, +25 p. 100, ns).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1988

[Validation of an self-measurement blood pressure device].

UNLABELLED: The aim of this study was to test the self-blood pressure (Self-BP) measurement device Copal UA-251 (Philips). This device uses auscultatory method for BP measurement. It was compared to reference methods: intraarterial and Hawksley Random Zero in 38 patients, selected in two groups: group RO (n = 18), compared Copal to Random Zero. 20 simultaneous measurements were recorded, with devices inversion at eleventh BP measurement, in 18 treated or untreated hypertensive patients. Group IA (n = 20) included 20 patients and compared Copal to intra-aortic measurement. Three simultaneous measurements were recorded, before a coronarography was performed, in 20 normo or hypertensive patients. RESULTS: (Table: see text). 1) A significant difference was recorded for SBP evaluated by Copal versus RO and for DBP measured by Copal versus IA. 2) A significant correlation was assessed between the different methods of measurement. 3) Differences between couples of RO-Copal values are not correlated to BP level, neither for SBP (r = 0.07), nor DBP (r = 0.05). Same results occur for IA-Copal values (SBP: r = 0.36, DBP: r = 0.30). 4) No order effect was found; no discrepancy between arms occurred in BP measurement. CONCLUSION: comparing intraaortic measure, Copal is efficient for SBP measurement, but overestimate DBP. Compared to R0, Copal overestimates SBP, but is efficient for DBP measurement. Regarding these results, a self-BP measurement is possible with this device.

Adolescent↗

PubMed1987

Treatment of mild to moderate hypertension with or without the converting enzyme inhibitor enalapril. Results of a six-month double-blind trial.

A group of 205 patients with mild to moderate essential uncomplicated hypertension was chosen from 3,183 hypertensive patients referred to a hypertension clinic for the first time, and was asked to participate in a six-month double-blind parallel trial. A single physician was in charge of all the patients. After a two-week single-blind placebo period, the patients were randomly assigned to regimens of either enalapril (20 mg per day) or placebo. Both groups were then followed up every two weeks, and increasing doses of hydrochlorothiazide (25 and 50 mg), oxprenolol (160 and 320 mg), and dihydralazine (50 and 100 mg) were added until the diastolic blood pressure was lower than 90 mm Hg. After a six-month follow-up, the enalapril group showed lower systolic and diastolic blood pressures than the control group (129/82 +/- 12/6 mg Hg versus 135/86 +/- 10/5 mm Hg; p less than 0.001). The number of daily tablets of active drugs was 2.7 +/- 1.8 in the enalapril group and 4.4 +/- 2.4 in the control group (p less than 0.01). The mean plasma potassium level was 4.16 +/- 0.4 mmol/liter in the enalapril group versus 3.92 +/- 0.4 mmol/liter in the control group (p less than 0.001), despite more frequent use of amiloride (p less than 0.001). This difference is explained by the lower dose of hydrochlorothiazide used in the enalapril group by comparison to the control group, and a lower excretion of urinary aldosterone in the enalapril group than in the control group (11.6 +/- 7.4 versus 19.8 +/- 11.8 micrograms per 24 hours, p less than 0.001). Drug withdrawal was necessary in eight patients in the enalapril group and in 16 patients in the control group (p less than 0.05). These results show that first-step treatment of mild to moderate uncomplicated essential hypertension with enalapril permits better blood pressure control than the standard treatment, requires fewer tablets to be taken daily, and involves a smaller risk of hypokalemia.

Adult↗

PubMed1987

Converting-enzyme inhibition buffers the counter-regulatory response to acute administration of nicardipine.

1. To investigate the interaction of angiotensin-converting-enzyme (ACE) inhibitor and calcium antagonist, we conducted a double-blind randomized, placebo-controlled crossover study of a new ACE inhibitor (CGS 14824 A, 20 mg) during intravenous administration (i.v.) of nicardipine in eight normotensive healthy subjects. Nicardipine was infused to give cumulative doses of 1.25, 3.75, and 8.75 mg after 10, 20 and 30 min. 2. ACE inhibition was demonstrated 24 h after the first CGS 14 824 A intake (61%). Three hours after the second dose this inhibition was more marked (98%). 3. I.v. nicardipine administration induced a significant and similar fall in systolic or diastolic blood pressure with and without ACE activity (-3/-6 vs -2/-8%), while tachycardia was significantly decreased by CGS 14 824 A (+14 vs +30%, P less than 0.02). The increase of plasma noradrenaline was also significantly blunted (+1.8 +/- 0.3 vs +3.1 +/- 0.7 pmol ml-1, P less than 0.05). 4. Active and total plasma renin increased at the end of nicardipine infusion in the presence or absence of ACE inhibition. Inactive renin did not increase after nicardipine infusion under placebo. It was higher 3 h after the second intake of CGS 14 824 A and then increased after nicardipine infusion. 5. The rise in plasma aldosterone during i.v. calcium antagonist infusion was diminished after ACE inhibition (126 +/- 39 vs 277 +/- 120 pmol l-1, P less than 0.02). 6. In conclusion, converting-enzyme inhibition buffers the rise in heart rate, plasma noradrenaline and plasma aldosterone induced by acute calcium blockade.

Adult↗

PubMed1987

Efficacy and influence on quality of life of enalapril as a first step treatment of hypertension.

205 patients with mild to moderate uncomplicated hypertension participated in a six-month double-blind parallel study performed in a unique center. After a two-week single-blind placebo period, the patients were randomly allocated to receive either Enalapril 20 mg once-a-day or placebo as the first step treatment. They were then followed-up every two weeks and successive doses of hydrochlorothiazide, oxprenolol, and dihydralazine were added until the diastolic pressure was lower than 90 mmHg. After six months, the systolic and diastolic blood pressures were lower in the Enalapril than in the control group (129/82 +/- 12/6 mmHg versus 136/86 +/- 10/5 mmHg; p less than 0.001). Drug withdrawal was necessary for 8 patients in the Enalapril group and for 16 patients in the control group (p less than 0.05). The number of daily tablets was 2.7 +/- 1.8 in the Enalapril group and 4.4 +/- 2.4 in the control group (p less than 0.01). Therefore, a stepped-care program based on Enalapril appears significantly more effective than a stepped-care program based on a diuretic.

Adult↗

PubMed1987

[Definition and consequences of blocking the renin-angiotensin system by converting enzyme inhibition].

46 patients (39 males), mean age 51 years (range 33-66), were randomly allocated to two different groups of treatment if their diastolic blood pressure was superior to 90 mmHg after a one-month treatment by 20 mg of enalapril. In the first group (ENA), 23 patients were given higher dosages of enalapril (40 and, if necessary 60 mg once-a-day). In the second group (HCTZ) 23 patients were given enalapril 20 mg and hydrochlorothiazide 25 and, if necessary, 50 mg once-a-day. Dosages were eventually increased after 2 weeks and evaluation of the results was performed after 4 weeks on treatment. Blood pressure was monitored in the supine position, at 3 minutes interval for thirty minutes, by an automatic device based on oscillometric method. Two successive measurements with a standard sphygmomanometer were performed by the physician at the end of the recording. No patient withdrew from the study nor was lost to follow-up. At the end of the study, 14 patients in the ENA group were receiving enalapril 60 mg once-a-day and 8 patients in the HCTZ group were receiving 50 mg of hydrochlorothiazide. Blood pressure was significantly lower in teh HCTZ group with the automatic device (130 +/- 9/80 +/- 8 vs 141 +/- 5/86 +/- 8 mmHg, p less than 0.01/p less than 0.05) and with the sphygmomanometer (134 +/- 10/89 +/- 6 vs 149 +/- 16/94 +/- 5 mmHg, p less than 0.001/p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1985

Systemic hypertension after cardiac transplantation: effect of cyclosporine on the renin-angiotensin-aldosterone system.

Fifteen patients who had undergone cardiac transplantation and who had hypertension (164 +/- 14/112 +/- 13 mm Hg), aged 16 to 57 years (mean 39), were treated with cyclosporine, 8 +/- 3 mg/kg/day, and prednisolone, 0.27 +/- 0.1 mg/kg/day, for 63 to 788 days (mean 288) after transplantation. They were not given antihypertensive drugs. Before treatment, the mean urinary sodium level was 104 +/- 48 mEq/day. Two discrete abnormalities accompanied their high blood pressure (BP): an increase in serum creatinine levels (p less than 0.05) to values exceeding those measured just before transplantation (2.1 +/- 1.0 vs 1.35 +/- 0.54 mg/dl) with low creatinine clearance (61 +/- 28 ml/min X 1.73 m2), and a 15% increase in plasma volume (+445 +/- 686 ml, p less than 0.02). Urinary excretion of vanilmandelic acid and total metanephrines was normal. Supine plasma renin activity was also normal (0.78 +/- 0.32 nmol/ml/hour). The stimulation of renin release after acute inhibition of converting enzyme by captopril was less marked than is usual in hypertensive subjects (0.86 +/- 0.54 nmol/liter/hour). Captopril induced a smaller drop in BP than nifedipine (-8 +/- 13/-6 +/- 10 mm Hg vs -14 +/- 11/-15 +/- 10 mm Hg). Levels of plasma aldosterone, angiotensinogen and converting enzyme activity were all normal, 308 +/- 147 pmol/liter, 712 +/- 164 nmol/ml and 30 +/- 6 mU/ml, respectively. It is concluded that hypertension is common in cardiac transplantation patients treated with cyclosporine, since 13 of our 15 subjects were normotensive before transplant.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1985

Assessment of the antimineralocorticoid effect of RU 28318 in healthy men with induced exogenous and endogenous hypermineralocorticism.

The antimineralocorticoid effect of a single dose of RU 28318, has been assessed in healthy men with exogenous or endogenous hypermineralocorticism. For exogenous hypermineralocorticism induced by ingestion of 9 alpha-fluorohydrocortisone (9 alpha-FHC) and aldosterone infusion, RU 28318 100 mg (9 alpha-FHC ingestion) or 200 mg (aldosterone infusion) was administered, and its effect compared with identical doses of spironolactone or a placebo. For endogenous hypermineralocorticism induced by ingestion of furosemide, RU 28318 100 and 300 mg was tested in comparison with 100 mg spironolactone or placebo. In all 3 studies, both RU 28318 and spironolactone significantly raised the urinary Na/K ratio when compared to placebo administration. No significant difference was apparent between RU 28318 and spironolactone. Thus, a single dose of RU 28318 in man has an antimineralocorticoid effect identical to those produced by the identical molar dose of spironolactone. In addition, the results show that furosemide-induced hyperaldosteronism constitutes a simple and reproducible test for assessing the antimineralocorticoid effect of a drug.

Adult↗

PubMed1985

[Predictability and prevention of hypokalemia induced by hydrochlorothiazide].

In a double blind study, 104 hypertensive patients were randomly allocated to two different stepped care programs for 6 months. Following a placebo run-in-phase, patients were given either Enalapril (EN) 20 mg once-a-day, or a Placebo (PL). Drugs were added as follow in a parallel stepwise sequence, until the goal blood pressure was obtained. First Hydrochlorothiazide (HCTZ) and then, if necessary, Oxprenolol (OXP) and Dihydralazine (DIH). The two goals of this study were to lower diastolic blood pressure below 90 mmHg and to maintain plasma potassium above 3.5 mmol/l. Amiloride was prescribed if plasma potassium was lower than 3.5 mmol/l. At the end of the study the EN group's blood pressure was 130 +/- 12/83 +/- 6 mmHg, the tablet's daily number was 2.6 +/- 1.8 and Amiloride was necessary in 15 patients. These parameters were significantly different from those observed in the Pl group (BP: 136 +/- 9/87 +/- 5 mmHg, tablets 4.2 +/- 2.4; amiloride necessary in 34 patients). The effects of HCTZ were evaluated in 32 patients previously treated by EN compared to 39 patients receiving PL. The converting enzyme inhibition minimized the fall in plasma potassium induced by HCTZ (3.6 t +/- 0.4 vs 3.3 +/- 0.5 mmol/l, p less than 0.05). Related to the HCTZ dose (mg/kg), the plasma potassium fall is lower in the EN group (0.46 +/- 1.1) than in the PL group (0.94 +/- 0.9, p less than 0.05). The plasma potassium reduction could not be predicted by age, plasma renin activity, plasma and urinary aldosterone or urinary kallikrein.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical Trials as Topic↗

PubMed1985

[Evaluation of the antihypertensive effect of capsule and tablet forms of nifedipine in moderate hypertension].

The antihypertensive effect of nifedipine which has a preferential antagonistic action in the calcium channels of vascular smooth muscle was studied in several series of patients. A preliminary double-blind placebo study in 7 moderate hypertensive patients showed that a 10 mg capsule of nifedipine induced a significant fall in systolic and diastolic pressures (max. - 14%) which persisted for 3 hours in ambulatory patients. A crossover trial against captopril (1 mg/kg) in 12 moderately hypertensive patients illustrated the antihypertensive effects of 2 capsules (20 mg) of nifedipine. The onset of action was faster and the effects, which were more intense than those of captopril, lasted several hours. A double-blind crossover trial against placebo was performed with 3 doses (20, 40, 60 mg) of a tablet form of nifedipine in 8 hypertensive patients. The degree and duration of the fall in blood pressure depended on the dosage: - 11% and 7 hours with 20 mg; - 14% and 10 hours with 40 mg and - 18% and 12 hours with 60 mg. This study demonstrated a direct relationship between the plasma concentration of nifedipine and the associated fall in mean blood pressure. Finally, in a chronic study of 20 hypertensive patients receiving 2 X 20 mg daily of the tablet form of nifedipine alone for 3 weeks, an 8% fall in blood pressure was observed, normalising the values in 50% of cases. Patients who remained hypertensive were given 2 X 40 mg of the nifedipine tablets for another 3 weeks and an additional 7% fall in blood pressure was observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Aldosterone↗