Attenuation and recovery of brain stem autoregulation in spontaneously hypertensive rats

Cerebral large arteries dilate actively around the lower limits of CBF autoregulation, mediated at least partly by nitric oxide, and maintain CBF during severe hypotension. We tested the hypothesis that this autoregulatory response of large arteries, as well as the response of arterioles, is altered in spontaneously hypertensive rats (SHR) and that the altered response reverts to normal during long-term antihypertensive treatment with cilazapril, an angiotensin-converting enzyme inhibitor. In anesthetized 6- to 7-month-old normotensive Wistar-Kyoto rats (WKY), 4- and 6- to 7-month-old SHR without antihypertensive treatment, and 6- to 7-month-old SHR treated with cilazapril for 10 weeks, local CBF to the brain stem was determined with laser-Doppler flowmetry and diameters of the basilar artery and its branches were measured through a cranial window during stepwise hemorrhagic hypotension. The lower limit of CBF autoregulation shifted upward in untreated SHR to 90 to 105 mm Hg from 30 to 45 mm Hg in WKY, and it reverted to 30 to 45 mm Hg in treated SHR. In response to severe hypotension, the basilar artery dilated by 21 +/- 6% (mean +/- SD) of the baseline internal diameter in WKY. The vasodilation was impaired in untreated SHR (10 +/- 8% in 4-mo-old SHR and 4 +/- 5% in 6- to 7-month-old SHR), and was restored to 22 +/- 10% by treatment with cilazapril (P < 0.005). Dilator responses of branch arterioles to hypotension showed similar attenuation and recovery as that of the basilar artery. The data indicate that chronic hypertension impairs the autoregulatory dilation of the basilar artery as well as branch arterioles and that antihypertensive treatment with cilazapril restores the diminished dilation toward normal.

Effect of cilazapril on ventricular remodeling assessed by Doppler-echocardiographic assessment and cardiac gene expression

The purpose of this study is to determine whether the administration of the ACE inhibitor cilazapril can lessen the adverse effects of ventricular remodeling, including systolic and diastolic dysfunction, modulation of fetal gene expression, increase of collagen genes, and depression of the sarcoplasmic reticulum (SR) Ca2+ ATPase gene in a myocardial infarcted (MI) rat model. At 1 day after MI, the animals were randomly assigned to cilazapril treatment or no treatment. We performed Doppler-echocardiographic examinations and measured cardiac mRNA in rats at 1 month and 3 months after MI (each group n = 8). The weights of the right (RV) and left ventricles (LV) in 1- and 3-month MI rats were significantly larger than those of the control rats. Cilazapril significantly prevented the increase. The MI rats showed systolic dysfunction, as evidenced by decreased fractional shortening (control, 34 +/- 3% vs. MI, 17 +/- 3%; P < 0.01) and ejection fraction measured by the modified Simpson's method (control, 61 +/- 2% vs. MI, 36 +/- 3%; P < 0.01) in rats at 1 month after operation. MI rats showed diastolic dysfunction, defined as increased peak early filling velocity, increased deceleration rate of the early filling wave, decreased late filling velocity, and an increase in the ratio of early filling to late filling velocity. Cilazapril significantly prevented systolic and diastolic dysfunction in rats after MI. The increases in beta-MHC, alpha-skeletal actin, ANP, and collagen I and III mRNAs in the nonischemic LV and RV were significantly suppressed by treatment with cilazapril. Depressed SR Ca(2+)-ATPase mRNA (nonischemic LV, 0.7-fold, P < 0.05 vs. control; RV, 0.5-fold, P < 0.05 vs. control) at 3 months after MI was significantly restored to normal levels by cilazapril. Cilazapril improved the adverse remodeling process by attenuating the progression of systolic and diastolic dysfunction, and prevented abnormal cardiac gene expression following MI.

Cilazapril and dietary gamma-linolenic acid prevent the deficit in sciatic nerve conduction velocity in the streptozotocin diabetic rat

Young adult male Hooded Wistar rats were rendered diabetic by administration of streptozotocin and maintained for 5 weeks on a diet containing either 6% olive oil as the total source of fat (OO diet), or purified gamma-linolenic acid (GLA) at a concentration of 0.5% with the remaining 5.5% provided by olive oil (GLA diet). Rats were treated with the angiotensin converting inhibitor, cilazapril, administered in the drinking water at a dose of 20 mg kg-1 body weight day-1. For the OO diet groups, sciatic nerve conduction velocity (NCV) in diabetic rats was reduced by 32% (p < 0.01) in comparison with nondiabetic (vehicle-treated) rats and 27.5% (p < 0.05) in comparison with diabetic rats treated with cilazapril. Diabetic, cilazapril-treated rats showed no reduction in NCV. For the nondiabetic, diabetic, and diabetic plus cilazapril groups fed GLA, the NCV was not significantly different, indicating that dietary GLA also prevented the deficit in the NCV induced by the diabetic state. Analysis of the sciatic nerve endoneurial phospholipid fatty acids revealed a significant reduction in the proportion of GLA and an elevation in the proportion of linoleic acid in the diabetic groups compared with the nondiabetic groups and this was independent of the cilazapril treatment or the dietary lipid supplement. Sciatic nerve myo-inositol content was unaltered while mannose, fructose, glucose, and sorbitol levels were elevated in the diabetic groups and these changes were independent of the cilazapril treatment or the dietary lipid supplement. These results indicate that in the rat, cilazapril treatment or dietary GLA, at the doses tested, are effective in preventing the deficit in the NCV induced by diabetes.

[Follow-up of patients with chronic aortic valve insufficiency with ACE inhibitor therapy]

Long-term treatment with ACE-inhibitors improves left ventricular function in patients with aortic regurgitation. But how does this advantage influence capacity? Using echocardiography and spiroergometry, we investigated 13 patients before and after a 3 month treatment with cilazapril (2.5-5 mg/d). Ventricular enddiastolic diameter-index decreased from 3.5 to 3.1 cm/m2 (p = 0.005), left ventricular endsystolic diameter-index from 2.3 to 2.0 cm/m2 (p = 0.005), and wallstress from 174 to 150 dyn/cm2 (p = 0.01). Left ventricular mass was reduced by 14% to 488 g (= 253 g/m2, p < 0.05). The regurgitant jet area decreased from 10.1 to 8.1 cm2 (p < 0.05). Wall thickness, workload, and maximal oxygen intake showed no significant difference during follow-up. These results indicate that left ventricular volumes and muscle mass in patients with aortic regurgitation are positively influenced by long term ACE-inhibition, which preserves exercise capacity.

Mechanism of decreased albuminuria caused by angiotensin converting enzyme inhibitor in early diabetic nephropathy

The mechanism of decreased albuminuria caused by an inhibitor of angiotensin converting enzyme (ACE) was investigated in patients with early diabetic nephropathy. The subjects were 10 patients with non-insulin-dependent diabetes mellitus without azotemia but with albuminuria (less than 650 mg/day). First, a two-week study was done: one week with a diet with ordinary sodium levels and one week with a sodium-restricted diet, in random order. The systemic blood pressure and urinary excretion of sodium and albumin were measured daily. Intrarenal hemodynamics, in terms of the resistance of afferent and efferent arterioles (RA and RE) and glomerular capillary pressure (PGC), were calculated from renal clearance, the plasma total protein concentration, and the pressure-natriuresis relationship. Results obtained before and two weeks after starting the ACE inhibitor cilazapril (2 mg/day) were compared. Urinary excretion of albumin was decreased by cilazapril in 8 of the 10 patients. Cilazapril decreased the RE [6830 (3680, 14,750) to 4660 (1750, 10,790) dynes.sec.cm-5, P < 0.05, mean (minimum, maximum)] and PGC (53 +/- 5 to 43 +/- 9 mm Hg, P < 0.02, mean +/- SD) in these 8 patients, but not in the two other patients. The RA was not significantly changed in any patient. The percent change caused by cilazapril in the urinary excretion of albumin was significantly correlated with the change in PGC (N = 10, r = 0.875, P < 0.01), but not with changes in the systemic blood pressure. In conclusion, the mechanism by which an ACE inhibitor caused a short-term decrease in albuminuria in early diabetic nephropathy involved a glomerular hemodynamic change, namely, a decrease in PGC.

ACE-inhibition prevents postischemic coronary leukocyte adhesion and leukocyte-dependent reperfusion injury

OBJECTIVE

Polymorphonuclear leukocytes (PMN), retained in the microvascular bed, can contribute to postischemic myocardial reperfusion injury. Since a beneficial effect of ACE-inhibition on reperfusion injury has been reported, we investigated the impact of cilazaprilat on PMN dependent reperfusion injury in isolated guinea pig hearts.

METHODS

Hearts (n = 5 per group) were subjected to 15 min of ischemia. Immediately thereafter, a bolus of PMN was injected into the coronary system. External heart work (EHW) and total cardiac nitric oxide release were measured. For microscopic evaluation, hearts received rhodamine 6G labelled PMN after ischemia, were arrested 5 min later and further perfused with FITC dextran (0.1%). Localization of retained PMN was assessed by fluorescence microscopy. Leukocyte activation was studied by FACS analysis of the adhesion molecule CD11b before and after coronary passage of the PMN. The ACE-inhibitor cilazaprilat (Cila, 2 microM) and the NO-synthase inhibitor nitro-L-arginine (NOLAG, 10 microM) were used to modulate nitric oxide formation of the heart.

RESULTS

Postischemic EHW recovered to 67 +/- 5% (controls) and 64 +/- 6% (Cila) of the preischemic value. Addition of PMN severely depressed recovery of EHW (39 +/- 2%) and NO release (39 +/- 6% of the preischemic value). Simultaneously, ischemia led to a substantial increase in postcapillary PMN adhesion (from 21 +/- 5 to 172 +/- 27 PMN/mm2 surface) and CD11b-expression of the recovered PMN (3-fold). Cila attenuated postischemic PMN adhesion (83 +/- 52 PMN/mm2) and activation of PMN, whereas it improved recovery of work performance (64 +/- 4%) and NO release (65 +/- 4%) in the presence of PMN. Conversely, NOLAG increased PMN adhesion (284 +/- 40 PMN/mm2) and myocardial injury. We conclude that ACE-inhibition prevents leukocyte dependent reperfusion injury mainly by inhibition of postcapillary leukocyte adhesion. The effect may be mediated by NO, given the proadhesive effect of NOLAG.

Angiotensin blockade improves cardiac and renal complications of type II diabetic rats

Using Otsuka Long-Evans Tokushima Fatty (OLETF) rats, a new model of human non-insulin-dependent diabetes mellitus (NIDDM), we examined the role of local angiotensin II in cardiovascular and renal complications of NIDDM. OLETF rats were orally given cilazapril (an angiotensin-converting enzyme inhibitor, 1 or 10 mg/kg), E4177 (an angiotensin AT1 receptor antagonist, 10 mg/kg), or vehicle for 26 or 40 weeks (from the age of 20 to 46 or 60 weeks). Cardiac mRNAs were measured by Northern blot analysis, and the thickening of the coronary arterial wall and the degree of perivascular fibrosis were determined by an image analyzer. Cilazapril or E4177 did not significantly affect body weight or plasma glucose and insulin levels of OLETF rats, indicating the minor effects on diabetes itself. However, both drugs significantly and similarly prevented coronary microvascular remodeling (the increase in wall thickening and perivascular fibrosis in coronary arterioles and small coronary arteries) in OLETF rats, and they were associated with the suppression of cardiac transforming growth factor-beta1 expression. Both drugs suppressed not only the increase in left ventricular weight but also the downregulation of cardiac alpha-myosin heavy chain expression in OLETF rats. Glomerulosclerosis and glomerular hypertrophy in OLETF rats were improved by cilazapril and E4177 to a comparable extent. These results, taken together with the fact that OLETF rats show normal plasma renin levels, support that the AT1 receptor is involved in the pathogenesis of cardiac and renal complications in NIDDM.

Effects of cilazapril and verapamil on myocardial iodine-125-metaiodobenzylguanidine accumulation in cardiomyopathic BIO 53.58 hamsters

Sympathetic nervous system activation is important in the pathophysiology of congestive heart failure. However, little about how the treatment for heart failure may influence myocardial sympathetic nervous activity has been established. In this study, we evaluated effects of cilazapril (CLZ) and verapamil (VER) on myocardial sympathetic nervous activity in cardiomyopathic BIO 53.58 hamsters using [125I]metaiodobenzylguanidine ([125I]MIBG).

METHODS

We used BIO 53.58 hamsters aged 3, 6 and 10 mo and age-matched normal F1b hamsters. We divided BIO 53.58 hamsters into untreated, CLZ- and VER-treated groups. We measured myocardial [125I]MIBG uptakes and norepinephrine concentrations and evaluated the extent of fibrosis and the distribution of [125I]MIBG.

RESULTS

The myocardial [125I]MIBG uptake was significantly lower in BIO 53.58 hamsters aged 6 and 10 mo than in age-matched F1b hamsters. Myocardial [125I]MIBG uptake was significantly correlated to myocardial norepinephrine concentration in BIO 53.58 hamsters. Myocardial [125I]MIBG uptake was significantly higher in both of the treated groups than in the untreated group. The extent of myocardial fibrosis was significantly lower in both of the treated groups than in the untreated group. The myocardial [125I]MIBG uptake showed a significant inverse correlation with the extent of fibrosis. Myocardial [125I]MIBG distribution was highly heterogeneous in the untreated BIO 53.58 hamsters, whereas it was homogeneous in the F1b hamsters aged 6 mo and the treated BIO 53.58 hamsters.

CONCLUSION

In BIO 53.58 hamsters, myocardial [125I]MIBG uptake decreased with the progression of cardiomyopathy, and the decreased uptake was improved by treatment with CLZ and VER. Thus, myocardial [125I]MIBG uptake can reflect the effects of treatment on cardiomyopathy, as well as the progression of cardiomyopathy.

Effect of angiotensin-converting enzyme inhibitors on the power spectrum of heart rate variability in post-myocardial infarction patients

BACKGROUND

Heart rate variability (HRV) time and frequency domain indices are strong predictors of malignant arrhythmias and sudden cardiac death. The effect of various angiotensin-converting enzyme (ACE) inhibitors on HRV in patients with acute myocardial infarction (AMI) has not been studied.

METHODS

Ninety patients with uncomplicated AMI (age range 39-75 years, median 61 years) were assigned randomly to six groups of 15 patients each. They were treated with placebo or one of the following ACE inhibitors for 30 days: captopril, cilazapril, enalapril, lisinopril or quinapril. HRV was assessed 3 days after the onset of AMI (baseline), and 30 days after treatment. Fifteen patients with stable coronary artery disease and 15 healthy volunteers, age- and sex-matched with AMI patients, served as controls.

RESULTS

At baseline, time and frequency domain HRV indices in the AMI groups were equally less than those in patients with stable coronary artery disease and normal volunteers. Compared with placebo, quinapril, lisinopril and captopril changed frequency domain HRV indices 30 days after initiation of treatment, indicating an increase in vagal tone, whereas enalapril and cilazapril had no significant effect on these indices. Most of the time domain HRV indices 30 days after initiation of treatment increased significantly in all patients treated with ACE inhibitors, but remained unchanged in the placebo group. Frequency domain and time domain HRV indices 30 days after treatment in the quinapril group did not differ statistically from those in patients with stable coronary artery disease, but were less than those in normal volunteers.

CONCLUSIONS

Quinapril, lisinopril and captopril improved frequency domain HRV indices related to vagal tone, whereas cilazapril and enalapril had no effect on these indices. This influence of some ACE inhibitors on HRV may be beneficial in reducing the risk for sudden death in post-myocardial infarction patients.

Effect of angiotensin converting enzyme inhibition [Cilazapril] on blood pressure recording in hypertensive obstructive sleep apneic patients

We investigated the efficacy of an Angiotensin Converting Enzyme [ACE] inhibitor on daytime and night-time blood pressure in 55 male hypertensive patients with moderately severe to severe obstructive sleep apnea. We resolved to determine if treatment oriented towards the reduction of hypertension would be successful, despite persistent repetitive hypoxemia and sleep-disordered breathing. The study was a randomized, double-blind, single daily dose, placebo-controlled protocol, with 8 days drug intake (placebo or 2.5 mg Cilazapril) and monitoring on the final day of drug administration. Subjects underwent continuous 24-h arterial blood pressure monitoring during baseline and treatment conditions. Polysomnography was performed at night during the 24-h arterial monitoring period. Cilazapril (2.5 mg) lowered systolic, diastolic and mean blood pressure, despite persistence of repetitive obstructive apneas during sleep and the associated repetitive hypoxemia. The lowering of blood pressure occurred without a significant change in heart rate, and was noted during nocturnal sleep, performance testing and graded exercise.

Glomerular hyperfiltration during sympathetic nervous system activation in early essential hypertension

Glomerular hyperfiltration may be important for the development of essential hypertension. Both the renin-angiotensin system and the sympathetic nervous system influence renal hemodynamic regulation. To test the hypothesis that glomerular hyperfiltration can be unmasked by sympathetic nervous system activation, renal hemodynamics and humoral components of the renin-angiotensin system were examined at rest and during mental stress in 45 young normotensive healthy subjects and 37 young people with mild essential hypertension. GFR and renal plasma flow (RPF) were determined with inulin and para-aminohippuric acid clearance at rest and during stress. At rest, RPF, GFR, filtration fraction, plasma renin activity, angiotensin (Ang) II concentrations, and serum aldosterone values were similar in normotensive and hypertensive subjects. After stress, blood pressure increased (P < 0.01), but this was nearly identical in normotensive and hypertensive subjects (7.05 +/- 6.9 versus 7.03 +/- 4.6 mmHg, NS). The decrease in RPF (-27 +/- 54 versus -22 +/- 25 ml/min per 1.73 m2, NS) was also similar in the two groups. In contrast, the increase in GFR (+ 10.5 +/- 7.2 versus 6.08 +/- 5.7 ml/min per 1.73 m2, P < 0.001) and filtration fraction (+2.48 +/- 1.38 versus 1.82 +/- 1.49%, P < 0.05) was more marked in hypertensive than in normotensive subjects. The concomitant increase in Ang II concentrations was greater in hypertensive than in normotensive subjects (+4.6 +/- 1.0 versus -1.0 +/- 0.45 pg/ml, P < 0.001). The increase in GFR during mental stress was correlated with the increment in Ang II concentrations (r = 0.39, P < 0.001). Compared with the placebo control phase, blockade of the renin-angiotensin system with an angiotensin-converting enzyme inhibitor attenuated the increase in GFR during stress in hypertensive (8.04 +/- 5.01 versus 10.1 +/- 5.7 ml/min per 1.73 m2, P < 0.05), but not in normotensive, subjects. Even in early essential hypertension, glomerular hyperfiltration is evident during sympathetic nervous system activation, which is mediated by postglomerular vasoconstriction. This early stress-induced glomerular hyperfiltration may contribute to, or trigger, the development of essential hypertension.

Ventricular functions in children with human immunodeficiency virus infection after ACE-inhibitors

Nine pediatric symptomatic patients infected with human immunodeficiency virus with elevated pulmonary arterial pressure (MPA pressure) and ejection fraction (EF); and with fractional shortening, (FS) mean velocity of circumferential fiber shortening (MVCfc) and left ventricular peak systolic wall stress (PS) were prospectively evaluated using 2-dimensional and M-mode serial echocardiography and Doppler cardiography after administration of an ACE inhibitor (Inhibace 0.025 mg/kg/D orally) for 12 weeks. The MPA pressure was not decreased, however the MVCfc and PS improved significantly (p < 0.05). Further, long term evaluation is required to determine its effect in preventing dilated cardiomyopathy and elevated mean pulmonary pressure.

Effects of cilazapril on ventricular arrhythmia in patients with congestive heart failure

Angiotensin-converting enzyme (ACE) inhibitors reduce mortality and morbidity in patients with congestive heart failure. These effects may be mediated, at least in part, by suppression of lethal ventricular tachycardia (VT). The aims of this study were to examine whether the ACE inhibitor cilazapril reduces ventricular arrhythmia in patients with congestive heart failure and, if cilazapril does reduce ventricular arrhythmia, to determine whether this reduction is associated with suppression of sympathetic nerve activity in these patients. Thirty-two congestive heart failure patients (left ventricular ejection fraction, 35 +/- 6%; New York Heart Association class II or III) with VTs (Lown grade IVa or IVb) were randomly assigned to receive either conventional therapy, consisting of diuretics and digitalis (control group), or conventional therapy plus cilazapril (cilazapril group). Twenty-four-hour ambulatory electrocardiographic monitoring was performed at baseline and after 2 months of therapy. Plasma norepinephrine levels and heart rate variability (standard deviation about the mean RR interval) were compared at baseline and after 2 months of treatment. The control group demonstrated no significant change in arrhythmia frequency after 2 months of treatment. In the cilazapril group, however, the number of ventricular couplets and VT runs was significantly decreased. In association with this reduction, plasma norepinephrine levels were decreased, and heart rate variability was increased. These results suggest that cilazapril has antiarrhythmic effects, which may be produced by suppressing high sympathetic activity, in patients with congestive heart failure. It should be noted that the study group was small and that, although ventricular dysrhythmia was reduced with therapy, it remained substantial. Further study is needed to verify these results and to determine the exact causes of the reduction.

Changes in left ventricular mass during treatment with minoxidil and cilazapril in hypertensive patients with left ventricular hypertrophy

Attainment of the regression of hypertension-associated left ventricular hypertrophy (LVH) seems to be a desirable goal of blood pressure (BP)-reducing therapy. Since antihypertensive drugs of differing types may exhibit markedly different abilities to modulate LVH, we examined the effects of the angiotensin-converting enzyme inhibitor cilazapril, and the potassium channel activator minoxidil, alone or in combination with each other, on the left ventricular mass (LVM) in patients with severe essential hypertension who had LVH detected by echocardiography. All patients received the same base therapy of bopindolol and guanfacine. After a run-in period, they were treated with: (1) cilazapril (n = 10); (2) minoxidil, combined with a diuretic (n = 10); or (3) both cilazapril and monoxidil (n = 6) for 12 months. The LVM index (LVMI; LVM per body surface area) was estimated every 3 months by means of echocardiography. Each kind of therapy decreased the arterial pressures to a similar degree. The 1-year treatment with the cilazapril-based regimen resulted in a significantly diminished LVMI (from a mean +/- s.d. of 173 +/- 38 to 152 +/- 22 g/m2; P < 0.05). On the other hand, the minoxidil-based therapy led to a significant increase in LVMI (from 148 +/- 19 to 170 +/- 35 g/m2; P < 0.05). There were no significant LVMI changes in patients receiving the combined, cilazapril + minoxidil-based treatment (172 +/- 34 vs the pretreatment 183 +/- 54 g/m2). The results confirm that long-term treatment with cilazapril is effective both in reducing BP and in reducing LVM. In spite of yielding a satisfactory reduction of BP, minoxidil therapy, even in combination with a diuretic and a beta-blocker, may lead to an aggravation of pre-existing LVH; this effect of minoxidil could be prevented by the simultaneous administration of cilazapril.

Renal dysfunction in glomerulonephropathy associated with rapid onset renal failure

Eight patients between the ages of 5 and 26 years developed a rapid decline of renal function with a period of oliguria or anuria which ranged between 1 and 21 days. The initial assessment of renal function revealed a severe degree of glomerular, tubular, and vascular abnormalities. The magnitude of the renal dysfunction was quantified and expressed in terms of a clinical score. The degree of glomerular and tubular dysfunction was inversely proportional to the renal plasma flow and peritubular capillary blood flow, respectively. Similar findings have been observed in a variety of other glomerulonephropathies where a relationship exists between the reduction of peritubular capillary blood flow and the severity of the tubulointerstitial disease. Evidence to support the position that the reduction of peritubular capillary blood flow plays a primary role in inducing tubulointerstitial disease is as follows: (i) A reduction of peritubular capillary blood flow has been documented in mesangial proliferative nephrosis with steroid resistance prior to the detection of tubulointerstitial disease. (ii) Ischemic insults are capable of inducing tubulointerstitial disease in the experimental setting of renal artery occlusion in animals. (iii) As demonstrated in the present report, an improvement of tubular function can be achieved following an increase in peritubular capillary blood flow with therapy designed to enhance renal perfusion.

Effects of medium-term antihypertensive therapy on haemostatic parameters in patients with essential hypertension

This study assessed the effects of the angiotensin-converting enzyme (ACE) inhibitor cilazapril on the main haemostatic variables in 22 patients, of either sex, with newly diagnosed uncomplicated essential hypertension. In the patients and in 10 control subjects, plasma levels of thrombomodulin, beta-thromboglobulin, D-dimer, tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI-1) had previously been measured. Only the levels of t-PA and PAI-1 were found to be higher than in controls. All these haemostatic evaluations were carried out after 6 and 12 months of treatment with an ACE inhibitor, cilazapril, 5 mg/day. This treatment significantly lowered the mean arterial pressure in the whole group from 133 to 106 mm Hg (after 6 months) and to 105 mm Hg (after 12 months), p < 0.05. No significant difference in any haemostatic parameters was observed after 6 and 12 months of treatment. The present study confirmed that treatment with cilazapril for 12 months lowers daytime ambulatory mean arterial pressure in patients with essential hypertension, without any significant increase in the tendency of blood to clot.

Albuminuria in diabetes mellitus: relation to ambulatory versus office blood pressure and effects of cilazapril

This study aimed to investigate the relationship between microalbuminuria and office blood pressure (BP) as compared with ambulatory BP in patients with diabetes mellitus under everyday practice conditions. It was also undertaken to assess the effect of the angiotensin converting enzyme inhibitor cilazapril on diabetes-associated albuminuria. Ambulatory BP was recorded during daytime in 54 patients with type II diabetes mellitus at the end of a 4-week period during which they received no vasoactive drug. The difference between office and ambulatory BP was unpredictable in the individual patient. There was no significant correlation between either ambulatory or office BP and urinary albumin/p5eatinine ratio. Fifty-one patients underwent a 40-week treatment with 5 mg/day of cilazapril. There was, in the absence of satisfactory BP control, the possibility of adding the calcium antagonist amlodipine (5 mg/day) from the 10th week onward and 12.5 mg/day of hydrochlorothiazide from the 20th week onward. Office mean BP was significantly reduced after 30 to 40 weeks of therapy in patients with normoalbuminuria (n = 19, -14%, P < .001), in those with microalbuminuria (n = 22, -6.6%, P < .01), as well as in those with clinical proteinuria (n = 9, -11.4%, P < .01). During the same time, the urinary albumin/creatinine ratio was not modified in normoalbuminuric patients (n = 19, +24.6%, P = .72) as well as in those with clinical proteinuria (n = 9, -29.4%, P = .09). On the other hand this value was significantly reduced for the group with microalbuminuria (n = 23, -24.3%, P < .05). In the overall population, as well as in hyperalbuminuric patients (patients with microalbuminuria + patients with clinical proteinuria), the reduction of the albumin/ creatinine ratio was also significant (n = 51, -7%, P < .01 and n = 32, -25,7%, P < .01, respectively). In conclusion, the findings of this study performed by practicing physicians show that ambulatory BP may differ greatly from office BP in diabetic patients. They also indicate that urinary albumin excretion is poorly correlated with office and ambulatory BP in type II diabetics. Finally, they demonstrate the antiproteinuric action of prolonged treatment with the angiotensin converting enzyme inhibitor cilazapril, whether given alone or combined with amlodipine.

Effect of antihypertensive treatment and N omega-nitro-L-arginine methyl ester on cardiovascular structure in deoxycorticosterone acetate-salt hypertensive rats

BACKGROUND

Deoxycorticosterone acetate (DOCA)-salt hypertensive rats exhibit a very severe degree of cardiovascular hypertrophy, which may in part be mediated by overexpression of the endothelin-1 gene.

OBJECTIVE

To examine the effects of the angiotensin I converting enzyme inhibitor cilazapril and of the calcium channel antagonist mibefradil, both of which may affect potential mechanisms responsible for hypertrophy of cardiovascular structures, and that of the nitric oxide synthase inhibitor N omega-nitro-L-arginine methyl ester (L-NAME), which may exert a paradoxical inhibitory effect on cardiovascular growth, on the severe cardiovascular hypertrophy of DOCA-salt hypertensive rats and on arterial expression of the endothelin-1 gene.

METHODS

Small-artery structure was examined on a wire myograph and endothelin-1 messenger RNA (mRNA) was quantified by Northern blot analysis.

RESULTS

Cilazapril did not affect blood pressure, cardiovascular structure or the increased abundance of endothelin mRNA of DOCA-salt hypertensive rats. Mibefradil treatment resulted in lower blood pressure, reduced cardiac hypertrophy, near-normal structure of conduit and small arteries and lower endothelin-1 mRNA abundance. L-NAME treatment resulted in higher blood pressure and increased severity of conduit artery hypertrophy, but reduced cardiac and small artery hypertrophy, and enhanced aortic endothelin-1 mRNA.

CONCLUSION

These results suggest that the renin-angiotensin system does not play a role in cardiovascular hypertrophy in DOCA-salt hypertensive rats, which is not unexpected since plasma renin is suppressed in these rats. Calcium channel blockade may interfere with mechanisms underlying vascular hypertrophy in this model via blockade of calcium entry or by reducing vascular endothelin-1 gene expression when the blood pressure is lowered. L-NAME has been shown to exert a growth-inhibitory effect on small arteries and on the heart despite increasing blood pressure, probably independently from its ability to inhibit nitric oxide synthase, the latter of which is presumably involved in the blood pressure rise induced.

Effect of antihypertensive treatment on lipids and fibrinogen: Greek multicentre study of cilazapril

The effect cilazapril (CLZ) treatment on serum lipids and fibrinogen was studied in 114 hypertensive patients for 18 weeks. Blood pressure, heart rate, lipid profile and fibrinogen were measured before and at the end of the study in all patients. Satisfactory blood pressure control was seen in 68% of the patients (group A) after 4 weeks of treatment with 5 mg CLZ monotherapy, while a single dose of chlorthalidone, 25 mg daily, was added to the therapeutic regimen of the remaining 32% of patients (group B) to achieve blood pressure control. We conclude that CLZ has a slight beneficial effect on the lipid profile and a significantly beneficial effect on fibrinogen, but its combination with a diuretic reverses this beneficial effect.

Long-term renal preservation in essential hypertension. Angiotensin converting enzyme inhibition is superior to beta-blockade

Antihypertensive treatment is known to slow down the decline in glomerular filtration rate (GFR) with time. Angiotensin converting enzyme (ACE) inhibition has been shown to be more effective in this regard than conventional antihypertensive therapy. In a recent prospective, randomized, double blind trial in 257 patients with essential hypertension, the loss of GFR, determined with 51Cr-EDTA clearance, was significantly less with an ACE inhibitor (cilazapril) than with a beta-adrenoceptor blocker (atenolol) during the first year of treatment. However, after 2 years, the two therapies were equally effective in this regard, thereby creating doubts about the long-term superiority of ACE inhibition in this regard. In order to elucidate whether the superior renal preservation with the ACE inhibitor was a transient effect, GFR was measured after 1 more year of treatment, i.e., after 36 months. At that time, the decline in GFR was significantly smaller in the ACE inhibitor group as compared to the beta-adrenoceptor blocker group (-3.0 [-5.5, -1.0; 95% CI] v -7.0 [-9.0, -4.5; 95% CI] mL/min x 1.73 m2; P = .026). This demonstrates that in the treatment of essential hypertension ACE inhibition preserves GFR significantly better than beta-adrenoceptor blockade during long-term therapy.

Evaluation of the sympathetic nervous system using heart rate variability and plasma hormones in hypertensive patients treated with cilazapril and atenolol

In a double-blind placebo-controlled parallel study, we assessed basal and post-therapeutic sympathetic activity both in supine and standing positions in mildly to moderately hypertensive patients by two different methods: frequency domain indices of heart rate variability (HRV) and plasma levels of both noradrenaline (NA) and its metabolite, 3,4-dihydroxyphenylglycol (DOPEG). Patients were evaluated on placebo and after 8 weeks of treatment with either cilazapril, 2.5-5 mg/day (13 patients) or atenolol, 50-100 mg/day (14 patients). Twenty-four-hour blood pressure was similarly reduced (p < 0.01) by both cilazapril and atenolol. Heart rate decreased with atenolol by 14 beats per min (p < 0.001) but did not change with cilazapril. When compared to the placebo, cilazapril did not modify sympathetic activity indices of HRV but did significantly reduce NA and DOPEG levels in both the supine and standing (p < 0.05) positions. As expected, atenolol reduced (p < 0.05) sympathetic activity indices of HRV but did not modify NA levels in either position. Moreover, while on placebo, patients showed no significant correlations between values of NA or DOPEG, nor in any of the HRV indices. We conclude that: (1) the antihypertensive effects of cilazapril and atenolol are similar, but in these patients, sympathetic activity indices showed divergent results both before and after therapy; (2) this may be due to different aspects of sympathetic activators, assessed independently by different methods, and (3) these discrepancies must be taken into account when evaluating autonomous nervous system parameters.

Adaptive changes in the acute haemodynamic effects of cilazapril during chronic treatment. Comparison with long-term clinical effect

OBJECTIVE

To study the adaptive changes in the acute haemodynamic response to ACE inhibition during chronic treatment in CHF.

METHODS

The acute and chronic effects of oral cilazapril (CLZ) treatment, an ACE-inhibitor with prolonged duration on haemodynamic measures (PCWP, PAP, RAP, CI and SVR) and clinical parameters (Quality-of-Life and NYHA class) were investigated in a double-blind, randomised, placebo-controlled trial in CHF. One hundred and thirty five patients (112 completing) in NYHA Classes II-III, on digitalis and diuretic treatment, were randomised after 2 weeks of placebo run-in, to receive either placebo or CLZ 0.5 mg, 1.0 mg or 2.5 mg daily for 12 weeks, followed by 2 week placebo wash-out. Haemodynamic studies, including exercise tests before and 3 h after medication, were performed on the first and last days of treatment. Measurements were performed at rest and at the maximum exercise level.

RESULTS

In ACEI-naive patients oral CLZ 0.5 and 1 mg/d caused a dose dependent decrease in PCWP and diastolic PAP, and a significant reduction of SVR mg. A slight increase in CI was observed in all groups. The maximum effect was observed 3-5 h post dose. After 12 weeks of oral treatment, the acute response was similar but was attenuated relative to the first dose. Exercise tolerance improved in a dose dependent manner. The NYHA classification remained unchanged or improved in the majority of patients. Entry into the 2.5 mg group had to be terminated at an early stage due to severe adverse events observed after the first dose.

CONCLUSION

During chronic treatment, the haemodynamic response to oral cilazapril was attenuated, indicating that continued clinical improvement in patients with CHF on CLZ is independent of to its acute haemodynamic effects.

[Effect of cilazapril in patients with essential hypertension: effect on cardiac hypertrophy]

Numerous antihypertensive drugs exist with different modes of action, which have a really effective impact on hypertension. The life expectancy of hypertensive patients is known to depend on the degree of damage caused to their target organs by the hypertension itself. Cardiovascular hypertrophy and its complications are considered to be among the major elements of this process. This work evaluates the effectiveness of the long-term treatment of essential hypertensive subjects (n = 10) with a long-acting ACE-inhibitor, cilazapril, as concerns their blood pressure and cardiac hypertrophy. Cilazapril given orally in a daily dose of 2.5 mg effectively lowered both the systolic (delta 30 mm Hg) and the diastolic (delta 19 mm Hg) blood pressure. No changes were found in body weight or heart rate, and only one side-effects (skin rash) was reported. Cilazapril considerably decreased the left ventricular mass and hence the hypertrophic index of hypertensive patients with cardiac hypertrophy, suggesting that ACE inhibitors are effective not only in lowering blood pressure and decreasing hypertrophy, but also in lowering the cardiac morbidity and mortality.

Effect of angiotensin converting enzyme inhibitor on chronic ischemic patients

Most of patients with cerebrovascular disease are associated with hypertension. Hypertension induces progressive atheromatous changes in cerebral arteries, and often causes steno-occlusive lesions of cerebral arteries. Angiotensin converting enzyme (ACE) inhibitor cilazapril is one of the antihypertensive drugs. It was reported that cilazapril improved resting cerebral blood flow (CBF) and cerebrovascular reserve capacity (CRC) in experimental studies. In this clinical study, the authors investigated whether long-term treatment with cilazapril could improve CBF and CRC in patients with steno-occlusive lesions of the major cerebral arterial trunk, measured by stable xenon computerized tomography (Xe-CT) with acetazolamide challenge. On the other hand, CBF and CRC in the calcium blocker-treated patients were measured in the same way. CBF did not change after long-term treatment with both cilazapril and calcium blocker. In the cilazapril-treated group, CRC was increased significantly (p < 0.05). However, CRC did not change in the calcium blocker-treated group. It was recognized that long-term treatment with cilazapril did not decrease CBF and improved CRC in patients with occlusive lesions of the major cerebral arterial trunk.