Antiproteinuric effect of the calcium channel blocker cilnidipine added to renin-angiotensin inhibition in hypertensive patients with chronic renal disease

Voltage-dependent N-type Ca2+ channels in endothelial cells contribute to oxidative stress-related endothelial dysfunction induced by angiotensin II in mice

N-type voltage-dependent Ca(2+)channels (VDCCs), expressed predominantly in the nervous system, play pivotal roles in sympathetic regulation of the circulatory system. Although N-type VDCCs are also reportedly expressed in the vasculature, their pathophysiological role is obscure. We demonstrated that oxidative stress-related endothelial dysfunction induced by angiotensin (Ang) II is suppressed in mice lacking the N-type VDCC α1B subunit (Cav 2.2). Impairment of endothelium-dependent relaxation of the thoracic aorta observed following Ang II treatment in wild-type (WT) mice was significantly attenuated in the Ang II-treated Cav 2.2-deficient mice, despite the comparable increase of the blood pressure in the two groups of mice. The thoracic aorta of the Cav 2.2-deficient mice showed a smaller positive area of oxidative stress markers as compared to the WT mice. The Ang II-induced endothelial dysfunction was also suppressed by cilnidipine, an L/N-type VDCC blocker, but not by amlodipine, an L-type VDCC blocker; however, this unique effect of cilnidipine was completely abolished in the Cav 2.2-deficient mice. Furthermore, selective inhibition of N-type VDCCs by ω-conotoxin GVIA dramatically suppressed the production of reactive oxygen species (ROS) as well as agonist-induced Ca(2+) influx in the vascular endothelial cells. These results suggest that N-type VDCCs expressed in the vascular endothelial cells contribute to ROS production and endothelial dysfunction observed in Ang II-treated hypertensive mice.

Comparison of effects of cilnidipine and azelnidipine on blood pressure, heart rate and albuminuria in type 2 diabetics with hypertension: A pilot study

Previous studies reported that both cilnidipine and azelnidipine have a renoprotective effect compared with amlodipine. The aim of this study was to compare the effects of cilnidipine and azelnidipine on blood pressure, heart rate and albuminuria. An open-label prospective crossover trial was carried out. We recruited 19 type 2 diabetics treated with amlodipine (5 mg/day) at least for 12 weeks. At study entry, amlodipine was changed to cilnidipine (10 mg/day) or azelnidipine (16 mg/day) and each administered for 16 weeks. Then, the drugs were switched and the treatment was continued for another 16 weeks. Despite no differences in 24-h blood pressure and heart rate between cilnidipine and azelnidipine, treatment with cilnidipine resulted in a greater reduction in urinary albumin:creatinine ratio than azelnidipine. Our results suggested that cilnidipine is more efficient in reducing albuminuria than azelnidipine independent of its blood pressure lowering effect in type 2 diabetic patients with hypertension. This trial was registered with UMIN (no. 000007201).

Switching to an L/N-type calcium channel blocker shows renoprotective effects in patients with chronic kidney disease: the Kyoto Cilnidipine Study

OBJECTIVE

This open-label, randomized controlled trial investigated the effects of cilnidipine, an L/N-type calcium channel blocker (CCB), in patients with chronic kidney disease (CKD).

METHODS

Sixty patients with CKD and well-controlled hypertension being treated with a renin- angiotensin system (RAS) inhibitor and an L-type CCB (L-CCB) were randomly assigned either to switch from the L-CCB to cilnidipine after a 4-week observation period or to continue with L-CCB treatment. Blood pressure, heart rate and renal function were monitored for 12 months. Data were available for analysis from 50 patients: 24 from the cilnidipine group and 26 from the L-CCB group.

RESULTS

Blood pressure was well controlled in both groups. After 12 months, proteinuria and heart rate were significantly decreased in the cilnidipine group, but proteinuria increased and heart rate remained unchanged in the L-CCB group. There was a significant positive correlation between the percentage changes in proteinuria and heart rate.

CONCLUSIONS

Cilnidipine has antihypertensive effects equivalent to those of L-CCBs. In patients with CKD, proteinuria can be decreased by switching from an L-CCB to cilnidipine, thereby improving renal function.

Excellent tolerance to cilnidipine in hypertensives with amlodipine - induced edema

Background:

Ankle edema is a common adverse effect of amlodipine, an L-type calcium channel blocker (CCB). Cilnidipine is a newer L/N-type CCB, approved for treatment of essential hypertension.

Aim:

This study was designed to determine whether cilnidipine can produce resolution of amlodipine-induced edema while maintaining adequate control of hypertension.

Materials and Methods:

A prospective study was performed on 27 patients with essential hypertension with amlodipine-induced edema. Concomitant nephropathy, cardiac failure, hepatic cirrhosis, or other causes of edema, and secondary hypertension were excluded by appropriate tests. Amlodipine therapy was substituted in all the cases with an efficacy-equivalent dose of cilnidipine. Clinical assessment of ankle edema and measurement of bilateral ankle circumference, body weight, blood pressure, and pulse rate were performed at onset of the study and after 4 weeks of cilnidipine therapy.

Results:

At completion of the study, edema had resolved in all the patients. There was a significant decrease in bilateral ankle circumference and body weight (P < 0.001). There was no significant change in mean arterial blood pressure and pulse rate.

Conclusions:

Therapy with cilnidipine resulted in complete resolution of amlodipine-induced edema in all the cases without significant worsening of hypertension or tachycardia. Cilnidipine is an acceptable alternative antihypertensive for patients with amlodipine-induced edema.

Predictive value of conjointly examined IL-1ra, TNF-R I, TNF-R II, and RANTES in patients with primary glomerulonephritis

Interleukin-1 receptor antagonist (IL-1ra), tumor necrosis factor soluble receptors (sTNF-R) type I and II, and regulated upon activation, normal T-cell expressed and secreted (RANTES) play an important role in the modulation of primary glomerulonephritis (GN) course. The aim of the study was to assess whether pre-treatment measurements of IL-1ra, sTNF-R, and RANTES assessed conjointly may be useful as predicting factors in patients with GN. In 84 patients (45 males and 39 female) serum concentration (pg/mL) and urinary excretion (pg/mgCr) of cytokines were measured. After 12 months of therapy with steroids and cyclophosphamide the patients were divided into two subgroups: Responders (R) and Non-Responders (NR) according to the treatment results. The urinary IL-1ra, TNF-RI and RII were significantly higher in R than NR (1,732 vs 646 with P < 0.001, 13.1 vs 6.3 with P = 0.005, and 33.6 vs 14.4 with P = 0.012). The urinary RANTES excretion was increased in NR (79.6 vs 28.5; P < 0.001). The multivariable analysis showed that if conjointly assessed, only urinary IL-1ra, TNF-R I and R II, RANTES with 85% probability pointed the feature remission (R). In conclusion, the urinary excretion of IL-1ra, TNF-R I and R II, and RANTES examined conjointly are effective in predicting favorable response to immunosuppressive treatment in patients with GN.

Comparison of the antialbuminuric effects of L-/N-type and L-type calcium channel blockers in hypertensive patients with diabetes and microalbuminuria: the study of assessment for kidney function by urinary microalbumin in randomized (SAKURA) trial

OBJECTIVE

To clarify whether the L-/N-type calcium channel blocker (CCB) cilnidipine is more renoprotective than the L-type CCB amlodipine in patients with early-stage diabetic nephropathy.

METHODS

In this prospective, multicenter, open-labeled, randomized trial, the antialbuminuric effects of cilnidipine and amlodipine were examined in renin-angiotensin system (RAS) inhibitor-treated patients with hypertension (blood pressure [BP]: 130-180/80-110 mmHg), type 2 diabetes, and microalbuminuria (urinary albumin to creatinine [Cr] ratio [UACR]: 30-300 mg/g).

RESULTS

Patients received cilnidipine (n = 179, final dose: 10.27 ± 4.13 mg/day) or amlodipine (n = 186, 4.87 ± 2.08 mg/day) for 12 months. Cilnidipine and amlodipine equally decreased BP. The UACR values for the cilnidipine and amlodipine groups were 111.50 ± 138.97 and 88.29 ± 63.45 mg/g, respectively, before treatment and 107.93 ± 130.23 and 89.07 ± 97.55 mg/g, respectively, after treatment. The groups showed similar changes for the natural logarithm of the UACR, serum Cr, and estimated glomerular filtration rate.

CONCLUSIONS

Cilnidipine did not offer greater renoprotection than amlodipine in RAS inhibitor-treated hypertensive patients with type 2 diabetes and microalbuminuria.

Comparison of the effects of cilnidipine and amlodipine on cardiac remodeling and diastolic dysfunction in Dahl salt-sensitive rats

OBJECTIVE

The L/N-type calcium channel blocker (CCB) cilnidipine suppresses sympathetic nerve activity and has a superior renoprotective effect compared with L-type CCBs such as amlodipine. The cardioprotective action of cilnidipine has remained largely uncharacterized, however. We have now investigated the effects of cilnidipine, in comparison with amlodipine, on cardiac pathophysiology in rats with salt-sensitive hypertension.

METHODS

Dahl salt-sensitive rats fed a high-salt diet from 6 weeks of age were treated with vehicle (LVH group), amlodipine (3 mg/kg per day), or cilnidipine (3 mg/kg per day) from 7 to 11 weeks.

RESULTS

The salt-induced increase in SBP apparent in LVH rats was attenuated to a similar extent by treatment with amlodipine or cilnidipine. The two drugs also similarly inhibited the development of left ventricular (LV) hypertrophy. However, cilnidipine attenuated the increase in relative wall thickness as well as ameliorated LV perivascular and interstitial fibrosis and diastolic dysfunction to a greater extent than did amlodipine. In addition, cilnidipine treatment was associated with greater inhibition of cardiac oxidative stress, inflammation, and renin-angiotensin system (RAS) gene expression. The decrease in cardiac norepinephrine content apparent in LVH rats was similarly inhibited by both drugs.

CONCLUSIONS

Cilnidipine attenuated LV fibrosis and diastolic dysfunction as well as LV concentricity to a greater extent than did amlodipine in Dahl salt-sensitive rats. The superior cardioprotective action of cilnidipine is likely attributable, at least in part, to the greater antioxidant and anti-inflammatory effects associated with inhibition of cardiac RAS gene expression observed with this drug.

Effects of valsartan on progression of kidney disease in Japanese hypertensive patients with advanced, predialysis, chronic kidney disease: Kanagawa Valsartan Trial (KVT)

Suppression of the renin-angiotensin system is known to slow progression of chronic kidney disease (CKD). However, few trials have been performed with Japanese patients. This study investigated whether the angiotensin receptor blocker (ARB) valsartan would delay the progression of kidney disease more effectively than conventional treatment in Japanese hypertensive patients with advanced, predialysis CKD. In a multicenter, randomized, open-label trial, 303 patients with hypertension and CKD with serum creatinine levels 2.0 mg dl(-1) were assigned to receive either conventional therapy plus valsartan (valsartan add-on group) or conventional therapy without ARB (control group). The primary outcome was a change in serum creatinine levels. Changes in urinary protein levels and time to onset of renal events were analyzed as secondary end points. There were no between-group differences in blood pressure during the study. Changes in serum creatinine and urinary protein levels did not differ between the groups. However, the rate of renal events, including doubling of serum creatinine levels or end-stage renal disease, was significantly lower in the valsartan add-on group than in the control group. The addition of valsartan decreased the risk by 42.6% after adjustment for baseline variables. The addition of valsartan to conventional therapy significantly slowed the rate of renal function decline and delayed the need for renal replacement therapy in Japanese hypertensive patients with advanced CKD.

Interaction of TNF with angiotensin II contributes to mitochondrial oxidative stress and cardiac damage in rats

Recent evidence suggests that tumor necrosis factor alpha (TNF) and angiotensin II (ANGII) induce oxidative stress contribute to cardiovascular disease progression. Here, we examined whether an interaction between TNF and ANGII contributes to altered cardiac mitochondrial biogenesis and ATP production to cause cardiac damage in rats. Rats received intraperitoneal injections of TNF (30 µg/kg), TNF + losartan (LOS, 1 mg/kg), or vehicle for 5 days. Left ventricular (LV) function was measured using echocardiography. Rats were sacrificed and LV tissues removed for gene expression, electron paramagnetic resonance and mitochondrial assays. TNF administration significantly increased expression of the NADPH oxidase subunit, gp91phox, and the angiotensin type 1 receptor (AT-1R) and decreased eNOS in the LV of rats. Rats that received TNF only had increased production rates of superoxide, peroxynitrite and total reactive oxygen species (ROS) in the cytosol and increased production rates of superoxide and hydrogen peroxide in mitochondria. Decreased activities of mitochondrial complexes I, II, and III and mitochondrial genes were observed in rats given TNF. In addition, TNF administration also resulted in a decrease in fractional shortening and an increase in Tei index, suggesting diastolic dysfunction. TNF administration with concomitant LOS treatment attenuated mitochondrial damage, restored cardiac function, and decreased expression of AT1-R and NADPH oxidase subunits. Mitochondrial biogenesis and function is severely impaired by TNF as evidenced by downregulation of mitochondrial genes and increased free radical production, and may contribute to cardiac damage. These defects are independent of the downregulation of mitochondrial gene expression, suggesting novel mechanisms for mitochondrial dysfunction in rats given TNF.

L/N-type calcium channel blocker cilnidipine reduces plasma aldosterone, albuminuria, and urinary liver-type fatty acid binding protein in patients with chronic kidney disease

Cilnidipine inhibits both L- and N-type calcium channels and has been shown to dilate efferent arterioles as effectively as afferent arterioles. We conducted an open-label, randomized trial to compare the effects of cilnidipine against those of amlodipine on blood pressure (BP), albuminuria, and plasma aldosterone concentration in hypertensive patients with mild- to moderate-stage chronic kidney disease. Patients with BP ≥130/80 mmHg, an estimated glomerular filtration rate of 90-30 ml/min/1.73 m(2), and albuminuria ≥30 mg/g, despite treatment with the maximum recommended dose of angiotensin II receptor blockers, were randomly assigned to two groups. Patients received either 10 mg/day cilnidipine (increased to 20 mg/day; n = 35) or 2.5 mg/day amlodipine (increased to 5 mg/day; n = 35). After 48 weeks of treatment, a significant and comparable reduction in systolic and diastolic BP was observed in both groups. The percent reduction in the urinary albumin to creatinine ratio and liver-type fatty acid binding protein (L-FABP) in the cilnidipine group was significantly greater than in the amlodipine group. Although plasma renin activity did not differ between the two groups, the plasma aldosterone level was significantly decreased in the cilnidipine group. Cilnidipine therefore appears to reduce albuminuria, urinary L-FABP, and plasma aldosterone levels more than amlodipine, and these effects are independent of BP reduction.

N-type calcium channel inhibition with cilnidipine elicits glomerular podocyte protection independent of sympathetic nerve inhibition

We recently demonstrated that cilnidipine, an L/N-type calcium channel blocker, elicits protective effects against glomerular podocyte injury, in particular, in obese hypertensive rats that express the N-type calcium channel (N-CC). Since the N-CC is known to be expressed in sympathetic nerve endings, we evaluated the reno-protective effects of cilnidipine in innervated and denervated spontaneously hypertensive rats (SHR). Male SHR were uninephrectomized and fed 4% high-salt diet (HS-UNX-SHR). Animals were divided into groups, as follows, and observed from 9 to 27 weeks of age: 1) vehicle (n = 14), 2) vehicle plus renal-denervation (n = 15), 3) cilnidipine (50 mg/kg per day, p.o.; n = 10), and 4) cilnidipine plus renal-denervation (n = 15). Renal denervation attenuated elevations in blood pressure, but failed to suppress urinary protein excretion and podocyte injury in HS-UNX-SHR. Cilnidipine in both innervated and denervated HS-UNX-SHR similarly induced significant antihypertensive effects, as well as suppressing the urinary protein excretion and podocyte injury, compared to vehicle-treated HS-UNX-SHR. These data indicate that renal nerves have a limited contribution to the cilnidipine-induced reno-protective effects in HS-UNX-SHR.

Renoprotective and antioxidant effects of cilnidipine in hypertensive patients

Cilnidipine, an L/N-type calcium channel blocker (CCB), has been reported to have more beneficial effects on proteinuria progression in hypertensive patients than amlodipine, an L-type CCB. The N-type calcium channel blockade that inhibits renal sympathetic nerve activity might reduce glomerular hypertension by facilitating vasodilation of the efferent arterioles. However, the precise mechanism of the renoprotective effect of cilnidipine remains unknown. Because cilnidipine exerted significantly higher antioxidant activity than amlodipine in cultured human mesangial cells, we hypothesized that cilnidipine might exert a renoprotective effect by suppressing oxidative stress. A total of 35 hypertensive patients receiving a renin-angiotensin system inhibitor were randomly assigned to a cilnidipine (n=18; 10 mg per day cilnidipine titrated to 20 mg per day) or amlodipine (n=17; 5 mg per day amlodipine titrated to 10 mg per day) group; the target blood pressure (BP) was set at 130/85 mmHg. After 6 months of treatment, systolic and diastolic BPs were significantly reduced in both of the groups, without any significant difference between the groups. The urinary albumin, 8-hydroxy-2'-deoxyguanosine (OHdG) and liver-type fatty-acid-binding protein (L-FABP) to creatinine ratios significantly decreased in the cilnidipine group (P<0.05) compared with those in the amlodipine group. The reductions in urinary albumin, 8-OHdG and L-FABP were not correlated with the change in systolic BP. In conclusion, cilnidipine, but not amlodipine, ameliorated urinary albumin excretion and decreased urinary 8-OHdG and L-FABP in the hypertensive patients. Cilnidipine probably exerts a greater renoprotective effect through its antioxidative properties.

Antialbuminuric advantage of cilnidipine compared with L-type calcium channel blockers in type 2 diabetic patients with normoalbuminuria and microalbuminuria

We evaluated the antialbuminuric advantage of cilnidipine, an N/L-type calcium channel blocker (CCB), compared with L-type CCBs in diabetic patients with normoalbuminuria and microalbuminuria. The study was a multicenter, non-randomized crossover trial. Participants were 90 type 2 diabetic patients exhibiting either normo- or microalbuminuria, and undergoing CCB treatment for ≥6 months prior to study entry. The CCB at the time of entry was continued for the first 6 months (Period 1). Treatment was subsequently switched from cilnidipine to an L-type CCB, or vice versa, for the second 6-month observation period (Period 2). During Period 1, the L-type CCB group showed a significant increase of urinary albumin excretion (UAE) over time, while the cilnidipine group showed no significant elevation. During Period 2, switching of the treatment from the L-type CCB to cilnidipine resulted in significant reduction of the UAE, whereas switching from cilnidipine to the L-type CCB resulted in no significant change in the UAE. This study demonstrated that the antialbuminuric effect of Cilnidipine, but not the L-type CCBs, was sustained even in patients treated for a long time. In addition, the antialbuminuric effect can be anticipated after switching from an L-type CCB to cilnidipine, but not vice versa.

Comparative effect of angiotensin II type I receptor blockers and calcium channel blockers on laboratory parameters in hypertensive patients with type 2 diabetes

BACKGROUND

Both angiotensin II type I receptor blockers (ARBs) and calcium channel blockers (CCBs) are widely used antihypertensive drugs. Many clinical studies have demonstrated and compared the organ-protection effects and adverse events of these drugs. However, few large-scale studies have focused on the effect of these drugs as monotherapy on laboratory parameters. We evaluated and compared the effects of ARB and CCB monotherapy on clinical laboratory parameters in patients with concomitant hypertension and type 2 diabetes mellitus.

METHODS

We used data from the Clinical Data Warehouse of Nihon University School of Medicine obtained between Nov 1, 2004 and July 31, 2011, to identify cohorts of new ARB users (n = 601) and propensity-score matched new CCB users (n = 601), with concomitant mild to moderate hypertension and type 2 diabetes mellitus. We used a multivariate-adjusted regression model to adjust for differences between ARB and CCB users, and compared laboratory parameters including serum levels of triglyceride (TG), total cholesterol (TC), non-fasting blood glucose, hemoglobin A1c (HbA1c), sodium, potassium, creatinine, alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyltransferase (GGT), hemoglobin and hematocrit, and white blood cell (WBC), red blood cell (RBC) and platelet (PLT) counts up to 12 months after the start of ARB or CCB monotherapy.

RESULTS

We found a significant reduction of serum TC, HbA1c, hemoglobin and hematocrit and RBC count and a significant increase of serum potassium in ARB users, and a reduction of serum TC and hemoglobin in CCB users, from the baseline period to the exposure period. The reductions of RBC count, hemoglobin and hematocrit in ARB users were significantly greater than those in CCB users. The increase of serum potassium in ARB users was significantly greater than that in CCB users.

CONCLUSIONS

Our study suggested that hematological adverse effects and electrolyte imbalance are greater with ARB monotherapy than with CCB monotherapy.

Long-term effects of calcium antagonists on augmentation index in hypertensive patients with chronic kidney disease: a randomized controlled study

BACKGROUND

Our previous retrospective study showed that benidipine was superior to amlodipine (AM) for reducing proteinuria and preserving the augmentation index (AI) in patients with chronic kidney disease (CKD).

METHODS

The present study enrolled CKD patients whose blood pressure was not well controlled by an angiotensin receptor blocker (ARB) and a calcium channel blocker other than AM or azelnidipine (AZ). Either AM (5 mg) or AZ (16 mg) was prescribed randomly. Clinical parameters, including proteinuria, serum creatinine, and AI, were measured before initiation of AM or AZ and 1 year later to assess the long-term effect on renal function and central blood pressure.

RESULTS

Brachial and central blood pressures were similarly reduced in both groups. However, pulse rate increased in the AM group, but decreased in the AZ group (+3 ± 1 vs. -2 ± 1 bpm, p < 0.0001). The reduction of proteinuria was greater in the AZ group (-29 ± 2 vs. -38 ± 3%, p < 0.01). Improvement of AI adjusted for a pulse rate of 75 bpm was larger in the AZ group than in the AM group (-4 ± 1 vs. -9 ± 1%, p < 0.05). In both groups, estimated GFR remained unchanged throughout the observation period.

CONCLUSION

In hypertensive patients with CKD, combined treatment with AZ and an ARB decreases proteinuria and preferentially improves arterial reflection.

Emerging drug combinations to optimize renovascular protection and blood pressure goals

Hypertension and renal disease are closely related. In fact, there is an inverse linear relationship between renal function and prevalence of hypertension. Hypertensive patients with renal dysfunction exhibit a poor clinical profile, which markedly increases their risk for cardiovascular outcomes. This review considers the available evidence on the best therapeutic approach for optimizing renovascular protection in the hypertensive population. To effectively reduce or at least slow the establishment and progression of renal disease in the hypertensive population it is critical to reach blood pressure targets. Many studies have shown that angiotensin-converting enzyme inhibitors and angiotensin receptor blockers prevent or at least delay the development of microalbuminuria in patients with hypertension and type 2 diabetes, reduce the incidence of overt diabetic nephropathy, and are also beneficial in patients with nondiabetic renal disease. Therefore, renin-angiotensin system (RAS) inhibition plays a key role in the prevention of renal outcomes. As the majority of patients with hypertension will need at least two antihypertensive agents to achieve blood pressure goals, the use of RAS inhibitors is a mandatory part of antihypertensive therapy. The question of which antihypertensive agent is the best choice for combining with RAS blockers should be considered. Many studies have shown that diuretics and calcium channel blockers are the best choice. However, more studies are needed to clarify the subgroups of patients who will benefit more from a combination with a diuretic or from a combination with a calcium channel blocker. To date, RAS inhibitors recommended in this context are angiotensin-converting enzyme inhibitors and angiotensin receptor blockers. Aliskiren, the first oral direct renin inhibitor available, has shown promising results.

Prevalence of chronic kidney disease and blood pressure control status in elderly hypertensive patients

OBJECTIVE

Hypertension guidelines recommend strict blood pressure (BP) control to less than 130/80 mmHg in patients complicated with chronic kidney disease (CKD). However, it is unclear whether this target BP level is applicable to the elderly hypertensive patients. The aim of this study was to assess the prevalence of CKD and BP control status in elderly hypertensive patients.

METHODS

Subjects were 675 hypertensive patients (65.5 ± 11.7 years, 290 males and 385 females). Prevalence of CKD and BP control status were compared between elderly and young/middle-age patients.

RESULTS

Average BP of elderly and young/middle-age patients were 134 ± 10/71 ± 9 mmHg and 131 ± 11/78 ± 9 mmHg, respectively. CKD was more prevalent in the elderly than in the young/middle-age patients (35.5% and 24.5%, respectively). The elderly patients with CKD were more likely to be males and older. They also required a greater number of antihypertensive drugs than those without CKD (2.4 ± 1.2 vs. 2.0 ± 1.1, p<0.01). Elderly patients without CKD who achieved a target BP of <140/90 mmHg were 73.2%. Similarly, 78.5% of the patients with CKD achieved BP of <140/90 mmHg, while those who achieved <130/80 mmHg were only 29.6%.

CONCLUSION

Our results suggest that CKD is frequently complicated in elderly hypertensive patients, and many of them failed to achieve strict BP goal in spite of the average use of 2.4 antihypertensive drugs.

A crossover comparison of urinary albumin excretion as a new surrogate marker for cardiovascular disease among 4 types of calcium channel blockers

BACKGROUND

At the intervention for cardiovascular disease (CVD), albuminuria is a new pivotal target. Calcium channel blocker (CCB) is one of the most expected agents. Currently CCBs have been classified by delivery system, half-life and channel types. We tested anti-albuminuric effect among 4 types of CCBs.

METHODS

Subjects were 50 hypertensives (SBP/DBP 164.7±17.1/92.3±12.2mmHg, s-Cr 0.81±0.37mg/dl, urinary albumin excretion (UAE) 69.4 (33.5-142.6) mg/gCr). Four CCBs were administered in a crossover setting: nifedipine CR, a long biological half-life L type by controlled release; cilnidipine, an N/L type; efonidipine, a T/L type; and amlodipine, a long biological half-life L type.

RESULTS

Comparable BP reductions were obtained. UAE at endpoints ware as follows (mg/gCr, *P<0.01): nifedipine CR 30.8 (17.3-81.1),* cilnidipine 33.9 (18.0-67.7),* efonidipine 51.0 (21.2-129.8), amlodipine 40.6 (18.7-94.7). By all agents, significant augmentations were observed in PRA, angiotensin I and angiotensin II (AngII). AngII at cilnidipine was significantly lower than that at amlodipine. PAC at cilnidipine and efonidipine was significantly lower than that at amlodipine. Nifedipine CR significantly reduced ANP concentration.

CONCLUSIONS

It is revealed that only nifedipine CR and cilnidipine could reduce albuminuria statistically. Thus, it is suggested that the 2 CCBs might be favorable for organ protection in hypertensives.

Cilnidipine, but not amlodipine, ameliorates osteoporosis in ovariectomized hypertensive rats through inhibition of the N-type calcium channel

Both osteoporosis and high blood pressure are major diseases in aging populations. Recent studies demonstrated that some antihypertensive drugs reduced the risk of bone fracture in elderly patients. Although calcium channel blockers (CCB) are widely used as first-line antihypertensive agents, there is no evidence that they prevent osteoporosis. In this study, we investigated the effects of two types of CCB on bone metabolism: cilnidipine (L-/N-type CCB), which suppresses norepinephrine release from the sympathetic nerve, and amlodipine (L-type CCB). In ovariectomized female spontaneous hypertensive rats, administration of cilnidipine, but not amlodipine, resulted in a significant increase in the ratio of alkaline phosphatase to tartrate-resistant acid phosphatase (TRAP) and a decrease in the number of osteoclasts, as assessed by TRAP staining in the proximal tibia. Bone mineral density, moreover, was significantly higher in the cilnidipine group as compared with the amlodipine group and was associated with a significant decrease in a urinary collagen degradation product (deoxypyridinoline). The degree of prevention of osteoporosis by cilnidipine was similar to that of carvedilol (a β-blocker) because β-blockers reduce fracture risks though the inhibition of osteoclast activation. Interestingly, these effects cannot be attributed to the reduction of blood pressure because all three drugs significantly decreased blood pressure. In contrast, both cilnidipine and carvedilol, but not amlodipine, significantly decreased heart rate, indicating that both cilnidipine and carvedilol suppressed sympathetic nervous activity. Overall, our present data showed that cilnidipine (L-/N-type CCB) ameliorated osteoporosis in ovariectomized hypertensive rats. These pleiotropic effects of antihypertensive drugs such as cilnidipine and carvedilol might provide additional benefits in the treatment of hypertensive postmenopausal women.

Angiotensin II receptor blocker and long-acting calcium channel blocker combination therapy decreases urinary albumin excretion while maintaining glomerular filtration rate

Microalbuminuria is a recognized risk factor and predictor for cardiovascular events in patients with hypertension. We analyzed changes in hypotensive effect, urinary albumin excretion (UAE) and estimated glomerular filtration rate (eGFR) in subjects with hypertension and microalbuminuria as a subanalysis of the results of the Nifedipine and Candesartan Combination (NICE-Combi) Study. A total of 86 subjects with essential hypertension with microalbuminuria (UAE <300 mg g(-1) creatinine) were randomly assigned in a double-blind manner to a combination therapy group (standard-dose candesartan at 8 mg per day plus controlled-release (CR) nifedipine 20 mg per day) (n=42) or an up-titrated monotherapy group (candesartan 12 mg per day) (n=44) for 8 weeks of continuous treatment after initially receiving standard-dose candesartan (8 mg per day) monotherapy for 8 weeks (initial treatment). After 8weeks, blood pressure (BP) was significantly reduced in both groups compared with at the end of initial treatment. UAE also showed a significant decrease in the combination therapy group, while there was no significant change of eGFR in either group. A significant positive correlation was seen between BP reduction and UAE after 8 weeks of double-blind treatment in both groups, whereas no significant association was found between ΔUAE and ΔeGFR in either group. These findings show that combination therapy with standard-dose candesartan and nifedipine CR is more effective than up-titrated candesartan monotherapy for reducing BP and improving UAE while maintaining eGFR, and strongly suggest that the combination of an angiotensin II receptor blocker and long-acting calcium channel blocker is beneficial in patients with hypertension and microalbuminuria.

Design and rationale of the study of assessment for kidney function by urinary microalbumin in randomized (SAKURA) trial

Recently, it has been demonstrated that L-/N-type calcium channel blockers (CCBs), cilnidipine, but not L-type CCB, decreased urinary protein in renin-angiotensin system (RAS), inhibitor-treated hypertensive patients with macroproteinuria. However, the antiproteinuric effect of cilnidipine was weaker in diabetic patients than in nondiabetic patients with macroproteinuria. This may be due to the fact that diabetic neuropathy was also developed in patients with advanced diabetic nephropathy because L-/N-type CCB has been considered to exert its renoprotetive effects through sympatholytic action. If so, the antiproteinuric effect of cilnidipine may be potent in patients with early stages of diabetic nephropathy. To elucidate our hypothesis, we designed a multi-center, open-labeled, randomized trial to compare the antialbuminuric effect between cilnidipine and amlodipine in RAS inhibitor-treated hypertensive (blood pressure [BP]: 130-180/80-110 mmHg) patients with type 2 diabetes and microalbuminuria (urinary albumin/creatinine [Cr] ratio: 30-300 mg/g). The primary study endpoint is the change in the urinary albumin/Cr ratio after a 1-year treatment. Enrollment began in April 2008 and was completed in March 2010. A total of 367 patients were randomly allocated to receive cilnidipine or amlodipine. At baseline, study subjects had 63.3± 8.5 years of age, 145.9 ± 12.2/80.8 ± 10.0 mmHg of BP, 101.0 ± 111.6 mg/g of urinary albumin/Cr. The trial is expected to show whether cilnidipine can exert an antialbuminuric effect in RAS inhibitor-treated hypertensive patients with early stages of diabetic nephropathy.

Mechanism by which chronic kidney disease causes cardiovascular disease and the measures to manage this phenomenon

In Japan, the number of chronic kidney disease (CKD) patients is thought to be 13,300,000, next in size after those with hypertension and diabetes. Although the number of patients with CKD seems large, it does not mean that all these patients require special treatment. Among them, nephrologists should pay special attention to patients with glomerular filtration rate below 50 mL/min/1.73 m(2) and progressive deterioration of renal function. Treatment of these CKD patients by a limited number of specialists is simply impossible; hence, it is essential to request treatment from physicians who are involved in general internal medicine and primary care. It is well known that not only does CKD cause end-stage renal failure, it also causes the onset of cardiovascular diseases (CVD) such as cardiac infarction and cerebral stroke; however, the question is how much significance does CKD have as a risk factor for CVD. It is understandable that hypertension and CVD are often complications of CKD; however, in addition to what is conventionally mentioned, there are three or four mechanisms that we would like to emphasize, and discuss herein. Among them, we would like to stress the role of klotho genes with special reference to the generation of CVD in CKD patients. When patients develop CKD, it is therefore necessary to remove as far as possible any factors that could represent a risk for CVD. Moreover, by taking appropriate measures against clinical conditions that often complicate CKD, such as hypertension, renal anemia, hyperuricemia, and hyperlipidaemia, the development of CVD can be prevented.

Beneficial effects of L- and N-type calcium channel blocker on glucose and lipid metabolism and renal function in patients with hypertension and type II diabetes mellitus

It has been proved that cilnidipine has N-type calcium channels inhibitory activity as well as L-type calcium channels and inhibits excessive release of norepinephrine from the sympathetic nerve ending. This study was undertaken to compare the efficacy of amlodipine (an inhibitor of L-type calcium channels) and cilnidipine (an inhibitor of both L-type and N-type calcium channels) in patients with hypertension and type II diabetes mellitus. Seventy-seven hypertensive patients were divided into two groups according to presence/absence of type II diabetes mellitus. In these two groups of patients, the effects of amlodipine and cilnidipine on glucose and lipid metabolism and renal function were compared. As for glucose and lipid metabolism, homeostasis model assessment insulin resistance (HOMA-R) level in the non-diabetic group and triglyceride in the diabetes group were significantly lower with cilnidipine than with amlodipine. As regards renal function in the diabetic group, estimated glomerular filtration rate (eGFR) was significantly higher and urinary albumin/creatinine ratio was significantly lower with cilnidipine than with amlodipine. Cilnidipine which inhibits N-type calcium channels is more useful for patients with hypertension and diabetes mellitus from its effects on glucose and lipid metabolism and renal function.

Metabolic syndrome and renal injury

Both metabolic syndrome (MetS) and chronic kidney disease (CKD) are major global health issues. Current clinical markers used to reflect renal injury include albuminuria and estimated glomerular filtration rate (eGFR). Given the same eGFR level, urine albumin might be a better risk marker to predict progression of CKD and future development of cardiovascular diseases (CVDs). Serum Cystatin C is emerging as a new biomarker for early detection of renal injury associated with MetS and cardiovascular risk. In addition to each component, MetS per se influences the incidence and prognosis of renal injury and the odds ratios increased with the increase in the number of metabolic abnormalities. Hyperinsulinemia, activation of rennin-angiotensin-aldosterone system, increase of oxidative stress, and inflammatory cytokines are proposed to be the plausible biological link between MetS and CKD. Weight control, stick control of blood pressure, glucose, and lipids disorders may lead to lessening renal injury and even the subsequent CVD.

Effects of an N-type calcium antagonist on angiotensin II-renin feedback

BACKGROUND

Interrupting the renin-angiotensin system (RAS) with an angiotensin II receptor blocker (ARB) has been found to induce RAS overactivation. In this study, we investigated the effect of 2 calcium channel blockers (CCBs), cilnidipine (L-/N-type CCB) and amlodipine (L-type CCB), on the RAS activation induced by an ARB in a strain of spontaneously hypertensive rats (SHR/Izm, 10 weeks of age).

METHODS

Rats intravenously catheterized for blood collection were randomly divided into groups that were administered the vehicle, the ARB valsartan or valsartan combined with one of the 2 CCBs. Their blood and kidneys were collected 270 min after administration.

RESULTS

Valsartan increased the plasma angiotensin II (Ang II) level in a dose-dependent manner. Cilnidipine suppressed the increase in plasma renin activity and plasma Ang II levels induced by valsartan, but amlodipine did not. Combined administration of cilnidipine, but not amlodipine, and valsartan significantly reduced the noradrenaline content in the renal cortex.

CONCLUSIONS

The results of this study suggest that the suppressive effect of cilnidipine on the valsartan-induced increase in RAS activity can be partly explained by its sympatholytic action mediated by N-type calcium channel blockade, and that combined administration of cilnidipine and valsartan might provide a synergistic therapeutic effect.

Comparison between the antiproteinuric effects of the calcium channel blockers benidipine and cilnidipine in combination with angiotensin receptor blockers in hypertensive patients with chronic kidney disease

AIMS

Benidipine, an L-/T-type calcium channel blocker, dilates renal efferent and afferent arterioles and reduces glomerular pressure; therefore, it may exert renoprotective effects. We conducted an open-labeled randomized trial to compare the effects of benidipine with cilnidipine in hypertensive patients with chronic kidney disease (CKD).

METHODS

The patients who were already being treated with angiotensin receptor blockers (ARBs) received one of the following treatment regimens: benidipine at a dose of 2 mg/day that was increased up to a dose of 8 mg/day (benidipine group; n=118) or cilnidipine at a dose of 5 mg/day that was increased up to a dose of 20 mg/day (cilnidipine group; n=115).

RESULTS

After 12 months of treatment, we observed a significant and comparable reduction in the systolic and diastolic blood pressure in both groups. The urinary protein:creatinine ratio was significantly decreased in both groups after 3 months of treatment and thereafter; however, the difference between both groups was not significant after 12 months of treatment. Benidipine exerted an antiproteinuric effect to a greater extent than cilnidipine in patients with diabetes.

CONCLUSION

The addition of benidipine as well as cilnidipine reduces urinary protein excretion in hypertensive patients with CKD who are already being administered ARBs.

L/N-type calcium channel blocker cilnidipine ameliorates proteinuria and inhibits the renal renin-angiotensin-aldosterone system in deoxycorticosterone acetate-salt hypertensive rats

Cilnidipine, an N/L-type calcium channel blocker, has been reported to inhibit sympathetic nerve activity and has a greater renoprotective effect than L-type calcium channel blockers. To investigate the hypothesis that cilnidipine might ameliorate advanced hypertensive nephropathy and inhibit the renal renin-angiotensin-aldosterone system, cilnidipine (1 mg per kg per day) or amlodipine (1 mg per kg per day) was administered to uninephrectomized deoxycorticosterone (DOCA)-salt hypertensive rats (DOCA-salt) for 4 weeks by gavage. Although the blood pressure in the DOCA-salt group was higher than that of control, neither cilnidipine nor amlodipine had any effect on the increase in blood pressure in the DOCA-salt group. The DOCA (40 mg per kg per week, subcutaneously (s.c.)) and salt (1% NaCl in drinking water) treatment significantly aggravated the levels of urinary protein excretion and creatinine clearance and increased glomerulosclerosis and collagen deposition in the tubulointerstitial area of the kidney. These effects were attenuated by cilnidipine treatment. Reverse transcription-polymerase chain reaction analysis revealed that the renal expression of mRNA for collagen I/IV and transforming growth factor-β was enhanced in the DOCA-salt group and that the overexpression of these molecules was suppressed by cilnidipine. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase-derived superoxide production in the kidney and urinary norepinephrine excretion, which were enhanced in the DOCA-salt group, were suppressed by cilnidipine. Cilnidipine also decreased the activity and expression of angiotensin-converting enzyme (ACE) and the aldosterone concentration in the renal homogenate. Although neither cilnidipine nor amlodipine had any effect on the increased blood pressure in the DOCA-salt group, these renal changes were not induced by treatment with amlodipine. In conclusion, cilnidipine inhibited renal dysfunction, sympathetic nerve activity and renal renin-angiotensin-aldosterone system in the DOCA-salt group.

T-type Ca channel blockade as a determinant of kidney protection

Voltage-dependent Ca channels are classified into several subtypes based on the isoform of their α1 subunits. Traditional Ca channels blockers (CCBs), including nifedipine and amlodipine, act predominantly on L-type Ca channels, whereas novel CCBs such as efonidipine, benidipine and azelnidipine inhibit both L-type and T-type Ca channels. Furthermore, cilnidipine blocks L-type and N-type Ca channels. These CCBs exert divergent actions on renal microvessels. L-type CCBs preferentially dilate afferent arterioles, whereas both L-/T-type and L-/N-type CCBs potently dilate afferent and efferent arterioles. The distinct actions of CCBs on the renal microcirculation are reflected by changes in glomerular capillary pressure and subsequent renal injury: L-type CCBs favor an increase in glomerular capillary pressure, whereas L-/T-type and L-/N-type CCBs alleviate glomerular hypertension. The renal protective action of L-/T-type CCBs is also mediated by non-hemodynamic mechanisms, i.e., inhibition of the inflammatory process and inhibition of Rho kinase and aldosterone secretion. Finally, a growing body of evidence indicates that T-type CCBs offer more beneficial action on proteinuria and renal survival rate than L-type CCBs in patients with chronic kidney disease (CKD). Similarly, in CKD patients treated with renin-angiotensin blockers, add-on therapy with N-type CCBs is more potent in reducing proteinuria than that with L-type CCBs, although no difference is found in the subgroup with diabetic nephropathy. Thus, the strategy for hypertension treatment with CCBs has entered a new era: treatment selection depends not only on blood pressure control but also on the subtypes of CCBs.

The N-type and L-type calcium channel blocker cilnidipine suppresses renal injury in Dahl rats fed a high-salt diet

The aims of the present study were to compare the effects of cilnidipine [L-type/N-type calcium channel blocker (CCB)] and amlodipine (L-type CCB) alone or in combination with the angiotensin II receptor blocker (ARB), valsartan, on blood pressure (BP), kidney function in Dahl salt-sensitive (DS) rats. DS rats fed a high-salt diet were divided into six groups; control (n = 13), two CCB (cilnidipine or amlodipine) groups at 1 mg/kg/day (n = 10), ARB (valsartan) at 10 mg/kg/day (n = 12), cilnidipine + valsartan (CV, n = 12), and amlodipine + valsartan (AV, n = 12). BPs were lower in the combination therapy groups than in those given either drug alone, but only CV inhibited the increase in urinary albumin excretion (UAE) and lowered the glomerular sclerosis score. In addition, AV elevated plasma renin activity and the angiotensin II concentration, and thus failed to inhibit increases in UAE and to lower glomerular sclerosis score. In conclusion, combination therapy with CCB and ARB decreases BP more effectively than either drug alone. When used in combination with valsartan, cilnidipine is more effective than amlodipine for preventing kidney injury.

Antiproteinuric effect of cilnidipine in hypertensive Japanese treated with renin-angiotensin-system inhibitors - a multicenter, open, randomized trial using 24-hour urine collection

Sustained proteinuria is an important risk factor for not only renal but also cardiovascular morbidity and mortality. Although inhibitors of the renin-angiotensin system (RAS) have been shown to reduce proteinuria. Monotherapy with those drugs is often insufficient for optimal blood pressure (BP)-lowering and therefore, combined therapy is needed. Recent reports suggested that cilnidipine, a dual L-/N-type calcium channel blocker, has renoprotective effect by dilating both efferent and afferent arterioles. In this study, a multicenter, open, randomized trial was designed to compare the antiproteinuric effect between cilnidipine and amlodipine when coupled with RAS inhibitors in hypertensive patients with significant proteinuria. Proteinuria was evaluated by 24-h home urine collection for all patients. A total of 35 proteinuric (>0.1 g/day) patients with uncontrolled BP (>135/85 mmHg) were randomized to receive either cilnidipine (n = 18) or amlodipine (n = 17) after a 6-month treatment with RAS inhibitors and were followed for 48 weeks. At baseline, the cilnidipine group was older and had lower body mass index (BMI) compared to the amlodipine group. After 32 weeks of treatment, diastolic blood pressure (DBP) was slightly, but significantly reduced, in the cilnidipine group, although systolic blood pressure (SBP) and mean BP did not differ. The urinary protein did not differ at baseline (cilnidipine group 0.48 g/day, amlodipine group 0.52 g/day); however, it significantly decreased in the cilnidipine group (0.22 g/day) compared to the amlodipine group (0.50 g/day) after 48 weeks of treatment. Our findings suggest that cilnidipine is superior to amlodipine in preventing the progression of proteinuria in hypertensive patients even undergoing treatment with RAS inhibitors.

Effect of cilnidipine on normal to marginally elevated urine albumin-creatinine ratio in asymptomatic non-diabetic hypertensive patients: an exponential decay curve analysis

BACKGROUND

High-normal urinary albumin excretion has been reported to have clinical significance with respect to progression of proteinuria and hypertension.

OBJECTIVE

We analysed the effect of cilnidipine (10 mg/day) on morning systolic blood pressure (SBP) and urine albumin-creatinine ratio (UACR) in 16 non-diabetic hypertensive patients with a normal to marginally elevated UACR (mean +/- SD 29.4 +/- 21.7; range 7.5-72.9 mg/g creatinine).

METHODS

Sequential home BP and UACR data were fitted to a simple exponential function as follows: where y is SBP (mmHg) or UACR (mg/g creatinine); alpha is the extent of the SBP (mmHg)- or UACR (mg/g creatinine)-lowering effect; beta (days) is the time-constant for SBP or UACR decrease; t is the number of days after the start of cilnidipine administration; and gamma is the finally stabilized SBP (mmHg) or UACR (mg/g creatinine).

RESULTS

Mean +/- SD morning SBP and UACR decreased by 20.4 +/- 11.4 mmHg and 15.2 +/- 13.1 mg/g creatinine, respectively, as determined by coefficient alpha. The mean +/- SD time-constant for UACR decrease was significantly longer than that for BP decrease (43.5 +/- 22.9 vs 15.4 +/- 7.1 days). UACR reduction correlated with pre-treatment UACR values (correlation coefficient [R] = 0.88, p < 0.01) but not with BP decrease.

CONCLUSIONS

The present study demonstrated that cilnidipine reduced UACR in hypertensive patients with normal to marginally elevated UACR independent of its BP-lowering effect.

Clinical effects of calcium channel blockers and renin-angiotensin-aldosterone system inhibitors on changes in the estimated glomerular filtration rate in patients with polycystic kidney disease

BACKGROUND

In the tubular cells of patients with polycystic kidney disease (PKD), a reduced intracellular Ca(2+) level accelerates cell proliferation, resulting in cyst formation. Thus, whether calcium channel blockers (CCB) are useful for the treatment of hypertension in patients with PKD is questionable.

METHODS

Thirty-two outpatients with autosomal dominant PKD (ADPKD) were treated at Tokyo Women's Medical University between 2003 and 2008; these patients were studied retrospectively. Periods during which the antihypertensive drug prescriptions for CCB and/or renin-angiotensin-aldosterone system inhibitors (RAAS-I; including angiotensin converting enzyme inhibitor and angiotensin II receptor blocker) had not been changed for at least 1 year and during which time a diuretic agent had not been prescribed were selected from among the clinical histories of the 32 outpatients. Consequently, 31 periods of 31 patients were analyzed, and mean treatment duration was 2.4 years in this study. The estimated glomerular filtration rate (eGFR) was used to evaluate renal function. To evaluate the influence of CCB and RAAS-I with respect to the decrease of the eGFR, analysis of covariance (ANCOVA), including confounding factors [baseline eGFR, mean systolic blood pressure (SBP), mean diastolic blood pressure (DBP)], was used. Only CCB significantly contributed to a reduction in ∆eGFR in both a univariable ANCOVA and a multivariable ANCOVA. None of the confounding factors, RAAS-I, the baseline eGFR, or blood pressure, contributed to reductions in ∆eGFR.

CONCLUSION

These results suggest that from a renoprotective perspective, CCB should possibly be avoided in patients with PKD unless treatment for resistant hypertension is necessary.

Cilnidipine suppresses podocyte injury and proteinuria in metabolic syndrome rats: possible involvement of N-type calcium channel in podocyte

OBJECTIVES

Clinical studies have indicated the beneficial effect of an L/N-type calcium channel blocker (CCB), cilnidipine, on the progression of proteinuria in hypertensive patients compared with an L-type CCB, amlodipine. In the present study, we examined the effects of cilnidipine and amlodipine on the renal injury in spontaneously hypertensive rat/ND mcr-cp (SHR/ND) and their underlying mechanism.

METHODS AND RESULTS

SHR/ND were treated with vehicle (nU10), cilnidipine [33 mg/kg per day, orally (p.o.); nU11] or amlodipine (20 mg/kg per day, p.o.; nU9) for 20 weeks. SHR/ND developed proteinuria in an age-dependent manner. Cilnidipine suppressed the proteinuria greater than amlodipine did. The immunohistochemical analysis showed that N-type calcium channel and Wilm's tumor factor, a marker of podocyte, were co-expressed. SHR/ND had significantly greater desmin staining, an indicator of podocyte injury, with lower podocin and nephrin expression in the glomeruli than Wistar-Kyoto rat or SHR. Cilnidipine significantly prevented the increase in desmin staining and restored the glomerular podocin and nephrin expression compared with amlodipine. Cilnidipine also prevented the increase in renal angiotensin II content, the expression and membrane translocation of NADPH oxidase subunits and dihydroethidium staining in SHR/ND. In contrast, amlodipine failed to change these renal parameters.

CONCLUSION

These data suggest that cilnidipine suppressed the development of proteinuria greater than amlodipine possibly through inhibiting N-type calcium channel-dependent podocyte injury in SHR/ND.

Therapeutic advantage of angiotensin-converting enzyme inhibitors in patients with proteinuric chronic kidney disease

Angiotensin-converting enzyme inhibitor (ACEI) or angiotensin receptor blocker (ARB) is recommended for the treatment of hypertension in patients with chronic kidney disease (CKD). The relation of ACEI to renal prognosis was investigated in CKD patients in a retrospective cohort study. The objectives were patients with nondiabetic CKD of stage 4 or below receiving monotherapy with calcium channel blocker (CCB), ACEI, or ARB, and combination therapy. For the endpoint of progression to CKD stage 5, Cox's proportional hazards analysis was conducted with explanatory variables of age, sex, baseline estimated GFR (eGFR), and proteinuria (UP) at the start of the observation period, and final blood pressure (BP) and UP at completion of the observation period. Analyzed patients comprised 131 males and 117 females, with mean age of 47.8 years. Patients were observed for 44.2 months, and the parameters of final SBP, DBP, eGFR, and UP were 127.6 +/- 6.9 mmHg, 77.8 +/- 5.8 mmHg, 38.1 +/- 10.6 ml/min/1.73 m(2), and 1.08 +/- 0.57 g/gCr, respectively, where 42 patients progressed to CKD stage 5. Drugs of CCB, ACEI, and ARB types were administered to 93, 85, and 127 patients, respectively. In the multivariate analysis, extracted common prognostic factors included the baseline eGFR and final UP, the odds ratio of which was 0.876 (every increase by 1 ml/min of eGFR) and 2.229 (every increase by 1 g of UP), respectively. Among drugs in use, ACEI was an independent prognostic factor, whose odds ratio was 0.147. The present study suggests that ACEI is a prognostic factor independent of hypotensive action and UP in CKD patients.

Renoprotective effect of calcium channel blockers in combination with an angiotensin receptor blocker in elderly patients with hypertension. A randomized crossover trial between benidipine and amlodipine

Anti-hypertensive medication with an angiotensin II receptor blocker (ARB) is effective in slowing the progression of chronic kidney disease. The present study was designed to investigate whether calcium channel blockers (CCBs) in combination with an ARB differentially affect kidney function. Elderly hypertensive patients with chronic kidney disease (n = 17, 72 +/- 6 years old) were instructed to self-measure blood pressure. They were randomly assigned to receive either benidipine (4-8 mg/day) or amlodipine (5-10 mg/day) combined with olmesartan (10 mg/day). After 3 months, CCBs were switched in each patient and the same protocol was applied for another 3 months. At baseline, significant correlation was obtained between urine albumin (22.8 +/- 16.7 (median +/- median absolute deviation) mg/g creatinine) and self-measured blood pressure (170 +/- 23/87 +/- 10 (mean +/- SD) mmHg, r = 0.65, p < 0.01). Both regimens reduced blood pressure to a similar extent (139 +/- 22/75 +/- 11 mmHg and 133 +/- 17/72 +/- 10 mmHg, respectively; both p < 0.001), while urine albumin decreased only after combination therapy including benidipine (11.7 +/- 6.1 mg/g creatinine, p < 0.05). Benidipine, but not amlodipine, in combination with olmesartan, reduced urinary albumin excretion in elderly hypertensive patients with chronic kidney disease. The results suggest the importance of selecting medications used in combination with ARB in hypertensive patients with chronic kidney disease.

The L/N-Type Calcium Channel Blocker, Cilnidipine, Reduces Heart Rate and Albuminuria in Patients with Type 2 Diabetes

This study was designed to investigate whether the L/N-type calcium channel blocker, cilnidipine, had a renoprotective effect compared with other calcium channel blockers. Twenty-five hypertensive patients with concomitant type 2 diabetes who had a urinary albumin-creatinine ratio (ACR) of 10 − 300 mg albumin/g creatinine and who had been treated with oral calcium channel blockers other than cilnidipine for more than 3 months were included. Patients' medication was changed to cilnidipine 10 mg/day or 20 mg/day without a washout period. Blood pressure and renal function were measured before and at 3 months after the new treatment. Heart rate was also determined as a marker for sympathetic nervous activity. After substitution of cilnidipine, blood pressure did not change significantly, but heart rate decreased significantly from 73.9 ± 7.1 beats/min to 72.0 ± 8.4 beats/min, and the log-transformed urinary ACR decreased to 82.9 ± 49.4% of baseline values. The changes in urinary ACR and heart rate showed a significant positive correlation. Thus, there was a strong indication that cilnidipine may exert its renoprotective effect by inhibiting sympathetic nervous activity.

Long-term blockade of L/N-type Ca(2+) channels by cilnidipine ameliorates repolarization abnormality of the canine hypertrophied heart

BACKGROUND AND PURPOSE

The heart of the canine model of chronic atrioventricular block is known to have a ventricular electrical remodelling, which mimics the pathophysiology of long QT syndrome. Using this model, we explored a new pharmacological therapeutic strategy for the prevention of cardiac sudden death.

EXPERIMENTAL APPROACH

The L-type Ca(2+) channel blocker amlodipine (2.5 mg.day(-1)), L/N-type Ca(2+) channel blocker cilnidipine (5 mg.day(-1)), or the angiotensin II receptor blocker candesartan (12 mg.day(-1)) was administered orally to the dogs with chronic atrioventricular block for 4 weeks. Electropharmacological assessments with the monophasic action potential (MAP) recordings and blood sample analyses were performed before and 4 weeks after the start of drug administration.

KEY RESULTS

Amlodipine and cilnidipine decreased the blood pressure, while candesartan hardly affected it. The QT interval, MAP duration and beat-to-beat variability of the ventricular repolarization period were shortened only in the cilnidipine group, but such effects were not observed in the amlodipine or candesartan group. Plasma concentrations of adrenaline, angiotensin II and aldosterone decreased in the cilnidipine group. In contrast, plasma concentrations of angiotensin II and aldosterone were elevated in the amlodipine group, whereas in the candesartan group an increase in plasma levels of angiotensin II and a decrease in noradrenaline and adrenaline concentrations were observed.

CONCLUSIONS AND IMPLICATIONS

Long-term blockade of L/N-type Ca(2+) channels ameliorated the ventricular electrical remodelling in the hypertrophied heart which causes the prolongation of the QT interval. This could provide a novel therapeutic strategy for the treatment of cardiovascular diseases.

Influence of T-calcium channel blocker treatment on deterioration of renal function in chronic kidney disease

Some calcium channel blockers (CCBs) have renoprotective effects. Our aim was to compare the effects of different subclasses of CCBs on the deterioration of renal function in chronic kidney disease (CKD). This is a prospective, observational cohort study in a single center. The subjects were 107 nondiabetic CKD patients. The rate of deterioration of estimated glomerular filtration rate (DeltaeGFR) was calculated by [last visit eGFR - baseline eGFR/follow-up duration]. Multivariate analysis was performed using the change in urinary protein (DeltaUP) and DeltaeGFR during follow-up as response variables. CCB subclasses were L-type in 76 patients, T- and L-type in 28 patients, and nondihydropyridines in 6 patients. Multiregression analysis indicated that higher baseline proteinuria (UP) and the use of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin II receptor blockers were associated with the decrease of UP, while the use of L-type CCBs, prednisolone, and probucol was associated with the increase of UP. The use of T- and L-type CCBs, ACEIs and diuretics was associated with a good outcome in terms of DeltaeGFR, whereas chronic glomerulonephritis, polycystic kidney disease, and higher baseline eGFR and UP were associated with a poor outcome. It is suggested that the use of T- and L-type CCB among other subclasses may improve the outcome of patients with nondiabetic CKD in terms of renal function.

Comparison of the antiproteinuric effects of the calcium channel blockers benidipine and amlodipine administered in combination with angiotensin receptor blockers to hypertensive patients with stage 3-5 chronic kidney disease

Benidipine, an L- and T-type calcium channel blocker, dilates both efferent and afferent arterioles and reduces glomerular pressure. Thus, it may exert renoprotective effects. We conducted an open-labeled, randomized trial to compare the blood pressure (BP)-lowering effect and antiproteinuric effect of benidipine with those of amlodipine in hypertensive patients with moderate-to-advanced-stage chronic kidney disease (CKD) (stages 3-5). These patients were already being administered the current maximum recommended doses of angiotensin receptor blockers (ARBs). Patients with BP >or=140/90 mm Hg, despite treatment with the maximum recommended dose of ARBs, were randomly assigned to two groups. The patients received either of the following treatment regimens: 4 mg day(-1) of benidipine, which was increased up to a dose of 16 mg day(-1) (B group; n=24), and 2.5 mg day(-1) of amlodipine, which was increased up to a dose of 10 mg day(-1) amlodipine (A group; n=23). After 6 months of treatment, a significant and comparable reduction in the systolic and diastolic BP was seen in both groups. The decrease in the urinary protein to creatinine ratio in the B group was significantly lower than that in the A group. Benidipine exerted antiproteinuric effect to a greater extent than did amlodipine, even in patients with diabetic nephropathy. We conclude that the addition of benidipine, rather than amlodipine, ameliorates urinary protein excretion in hypertensive patients with CKD who are already being administered ARBs. Therefore, we propose a combination therapy with benidipine and ARBs, even for patients with moderate-to-advanced-stage CKD.