Hideyuki Oniki

Kyushu Medical Center, Hukuoka, Fukuoka, Japan

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Publications (22)49.51 Total impact

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    ABSTRACT: Among the several methods used to assess salt intake, estimating 24 h urinary salt excretion by spot urine seems appropriate for clinical practice. In this study, we investigated variability in urinary salt excretion using spot urine in hypertensive outpatients. Participants included 200 hypertensive patients who underwent spot urinary salt excretion at least three times during the observation period. Mean urinary salt excretion and the coefficient of the variation were 8.62 ± 1.96 g/day and 19.0 ± 10.2%, respectively. In the analysis of participants who underwent assessment of urinary salt excretion at least eight times (n = 54), a significant reduction in mean urinary salt excretion was found at the 5th measurement. On the contrary, the coefficient of the variation of urinary salt excretion continued to increase until the 5th measurement, and became stable thereafter. Mean urinary salt excretion was positively correlated with mean clinic diastolic blood pressure (r = 0.27, p < 0.05). Clinic diastolic blood pressure in the high urinary salt excretion group (≥10 g/day) was significantly higher than that of the low group (76.2 ± 7.5 vs 73.4 ± 8.3 mmHg, p < 0.05). Mean urinary salt excretion in summer was significantly lower than that of the other seasons (7.75 ± 1.94 vs 9.09 ± 2.68 (spring), 8.72 ± 2.12 (autumn), 8.92 ± 2.17 (winter) g/day, p < 0.01). In conclusion, repeated measurements of urinary salt excretion using spot urine are required to assess daily salt intake of hypertensive patients.
    No preview · Article · Aug 2015 · Clinical and Experimental Hypertension
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    ABSTRACT: Assessing an individual's salt intake is necessary for providing guidance with respect to salt restriction. However, the methods that exist for assessing salt intake have both merits and limitations. Therefore, the evaluation methods should be selected for their appropriateness to the patients and the environment of the medical facilities. The purpose of the present study was to investigate the validity of a brief self-administered diet-history questionnaire (BDHQ) by comparing the responses with 24-h urinary salt excretion. A total of 136 hypertensive outpatients (54 men and 82 women) were included in this study. All subjects were given the BDHQ and performed 24-h home urine collection. The energy-adjusted salt intake as assessed by the BDHQ was 12.3 (95% confidence interval: 11.8-12.9) g per day, and the urinary salt excretion evaluated by 24-h urinary collection was 9.0 (8.4-9.5) g per day. The energy-adjusted salt intake assessed by the BDHQ correlated significantly with the urinary salt excretion evaluated by 24-h urinary collection (r=0.34, P<0.001). In conclusion, the estimated salt intake evaluated by the BDHQ weakly, but significantly, correlated with 24-h urinary salt excretion. In clinical practice, it seems important to utilize both methods to assess an individual's salt intake in order to provide adequate guidance for salt restriction.Hypertension Research advance online publication, 19 March 2015; doi:10.1038/hr.2015.35.
    No preview · Article · Mar 2015 · Hypertension Research
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    ABSTRACT: Several studies have documented an association between serum uric acid (SUA) concentration and cardiac hypertrophy in hypertensive patients; however, the association remains unclear in chronic kidney disease (CKD) patients. If there is an association between SUA and hypertrophy in these patients, it is unknown whether the association is different between men and women. Our aim in this study is to determine whether SUA is associated with cardiac hypertrophy in CKD patients, focusing on any sex differences. Two hundred sixteen CKD patients (117 men and 99 women) were enrolled in this cross-sectional study. Patients prescribed uric acid-lowering agents and those with congestive heart failure, valvular heart disease, or ischemic heart disease were excluded from this study. Left ventricular mass index (LVMI) and left ventricular hypertrophy (LVH) were assessed using echocardiography. The prevalence of LVH was 58% in men and 47% in women. In multivariate linear regression analysis, SUA levels did not correlate with LVMI in men, whereas SUA was independently associated with LVMI in women (β=0.27, P=0.02). Multivariate logistic regression analysis also revealed that diabetes mellitus (odds ratio (OR), 4.41; P=0.01) was associated with LVH in men, whereas age (OR, 1.13; P<0.01), hypertension (OR, 7.38; P=0.03) and SUA (OR, 1.91; P=0.03) were associated with LVH in women. In female CKD patients, SUA levels were associated with LVMI and LVH, whereas there was no association in male patients. These observations suggest that an association between SUA levels and the development of cardiac hypertrophy is more likely in women than in men.Hypertension Research advance online publication, 3 October 2013; doi:10.1038/hr.2013.134.
    No preview · Article · Oct 2013 · Hypertension Research
  • Yuko Ohta · Takuya Tsuchihashi · Kanako Kiyohara · Hideyuki Oniki
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    ABSTRACT: Objective: Uric acid (UA) has shown to be a causal risk factor for the development and progression of renal disease. The aim of this study was to investigate the relationship between changes in the level of UA and trends in the renal function among hypertensive patients during a 10-year observation period. Methods: The subjects included 104 hypertensive outpatients (60 women and 44 men, mean age 60±9 (SD) years at the first visit) who had undergone at least five instances of successful 24-hour home urine collection, with the first examination completed between 1998 and 2000 and the last examination completed between 2008 and 2010. Results: The estimated glomerular filtration rate (eGFR) significantly decreased over the 10.4-year observation period, with an average change in eGFR of -0.66/mL/min/year. The uric acid clearance at the last examination was significantly lower than that observed at the first visit, while there were no significant differences in the serum UA levels during this period. The change in serum UA exhibited a significant negative correlation with the change in eGFR (r=-0.34, p<0.01). The patients whose UA level decreased more than 0.5 mg/dL during the observation period demonstrated significantly smaller declines in eGFR compared to those whose UA level increased more than 0.5 mg/dL. In the multivariate analysis, the change in serum UA and the average urinary salt excretion during the observation period were found to be significantly associated with the change in eGFR, independent of age, sex, BP changes or an increased number of antihypertensive drugs. Conclusion: Based on the findings observed over a 10-year observation period, increased UA is suggested to promote decline of the renal function in hypertensive patients. Controlling the level of UA as well as intensively restricting salt intake is required in order to preserve the renal function.
    No preview · Article · Jul 2013 · Internal Medicine
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    ABSTRACT: Perioperative blood pressure (BP) management is important to prevent cardiovascular complication, especially for hypertensive patients. In the present study, we investigated perioperative BP variability and contributing factors in hypertensive patients. Subjects were 28 treated hypertensive patients who underwent total or subtotal gastrectomy. Ambulatory BP monitoring was carried out before and after (16 days in average) the surgery. Angiotensin converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), and diuretics were withdrawn on the previous day, while other drugs were administered until the day of surgery. BP, body weight, blood chemistry, as well as the use of intravenous vasopressor or vasodepressor agents during the perioperative period were investigated. The 24-hour BP before surgery was 124 ± 19/70 ± 12 mm Hg, and the number of antihypertensive drugs was 1.8. In 22 patients, intravenous vasopressor agents were used during surgery, while another patient received intravenous vasodepressor agents after surgery. The 24-hour BP significantly decreased after surgery (-8.2 ± 14.7/-2.6 ± 7.3 mm Hg). Body weight, serum Na, and hematocrit also decreased. There were nine patients whose 24-hour systolic BP decreased by more than 10 mm Hg and for two patients more than 20 mm Hg. The decrease in BP correlated with the change in serum Na. Forty-three percent of the patients who took ACE inhibitors/ARBs showed BP reduction greater than 10 mm Hg, while 25% of the patients without these drugs showed such BP reduction. Our findings suggest that 24-hour BP decreases after gastrectomy. Patients taking ACE inhibitors or ARBs may need careful monitoring to prevent excessive BP fall.
    No preview · Article · Mar 2013 · Clinical and Experimental Hypertension
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    Yuko Ohta · Takuya Tsuchihashi · Kanako Kiyohara · Hideyuki Oniki
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    ABSTRACT: We investigated the influence of long-term salt load on renal function in hypertensive patients. The subjects were 133 hypertensive patients (80 women and 53 men, mean age 60±9 years) who underwent at least five successful 24 h home urine collections during the 10-year observation period. Blood pressure (BP) and 24-h urinary salt and creatinine excretion levels were measured. BP decreased from 143±12/85±8 to 129±14/68±11 mm Hg during the 10.5-year observation period, and this decrease was associated with patients taking an increased number of antihypertensive drugs (1.3±1.0 to 2.2±1.1). The estimated glomerular filtration rate (eGFR) also significantly decreased from 71.7±14.6 to 64.7±16.5 ml min(-1) (P<0.01), and the change in eGFR was -0.68 ml min(-1) per year on average. The average salt excretion was 8.6±2.2 g per day and showed a significant negative correlation with the change in eGFR (r=-0.21, P=0.02). Subjects with an average salt excretion<8 g per day showed a significantly slower decline in renal function than those with an average salt excretion 8 g per day (the change in eGFR: -0.41±1.10 vs. -0.83±1.19 ml min(-1) per year, P<0.05). In the multivariate analysis, the average salt excretion (partial r=-0.19, P=0.03) and baseline eGFR (partial r=-0.23, P=0.01) were significantly associated with the change in eGFR. This association was independent of BP change or an increased number of antihypertensive drugs. The results suggest that long-term salt load promotes a decline in renal function in hypertensive patients; thus, salt restriction is encouraged, to prevent renal damage.Hypertension Research advance online publication, 11 October 2012; doi:10.1038/hr.2012.155.
    Preview · Article · Oct 2012 · Hypertension Research
  • Hideyuki Oniki · Takuya Tsuchihashi · Kanako Kiyohara · Yuko Ohta
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    ABSTRACT: Objectives: We examined chronological changes in salt intake in Japanese hypertensive patients. Methods: Subjects were 1,671 hypertensive patients (mean age 57.6 years; 761 males, 910 females) who visited the division of Hypertension, National Kyushu Medical Center, Fukuoka, Japan from 1998 to 2011. The 24-h urine was collected at home using a proportional urine-sampling device. Subjects collected 24-h urine 3.7 times in average and 6,137 urine samples in total were used for analysis. Results: Mean 24-h salt excretion, blood pressure and proteinuria in 1998 were 9.8 +/- 4.0 g/day, 143 +/- 11/87 +/- 7 mmHg, and 0.6 +/- 0.9 g/day, respectively. In 2011, salt excretion decreased to 8.6 +/- 3.3 g/day, blood pressure to 129 +/- 12/70 +/- 12 mmHg, and proteinuria to 0.2 +/- 0.7 g/day (p < 0.01). Achievement rate of salt reduction (<6 g/day) in 1998 was 12.6%, which increased to 20.8% in 2011. Salt excretion showed a weak negative correlation with age, and a positive correlation with body weight (r = 0.33, p<0.01). Males (N = 2,759) showed higher salt excretion (10.0 +/- 4.0 g/day) than females (8.2 +/- 3.2 g/day, N = 3,378). Among 738 patients who collected urine at least twice, subjects who successfully reduced salt excretion to less than 6 g/day at the final measurement (N = 165) showed significant reductions in systolic blood pressure (-13.0 +/- 19.4 mmHg vs -9.1 +/- 18.2 mmHg, p<0.05) and proteinuria (-0.21 +/- 1.06 g/day vs -0.03 +/- 0.76 g/day, p<0.05), as compared with those whose salt excretion were consistently higher than 6 g/day (N = 500). Conclusions: Although repeated measurements of 24-h salt excretion are effective to reduce salt intake and blood pressure control in hypertensive patients, further efforts are required to improve the achievement rate of salt reduction.
    No preview · Article · Sep 2012 · Journal of Hypertension
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    ABSTRACT: Objectives: To investigate perioperative blood pressure(BP) changes in the outpatients with cataract surgery. Design and Methods: Forty-one outpatients (mean age 71.2 +/- 7.2 years) who visited an ophthalmologic clinic for cataract surgery were enrolled. Sitting BP was measured at the clinic visit before surgery(Clinic BP). On the day of surgery, BP was measured 1 hour before surgery (Pre BP).During the surgery, BP was measured every 5 minutes. Clinic BP and Pre BP were averaged and defined as baseline BP. First 3 BP measurements during surgery were averaged and defined as operative BP.Max BP was the maximum BP values during surgery.Characteristics, pharmacological records and blood chemistry of the patientswere collected.The predictive ability of baseline BP for excessive operative BP elevation was evaluated using receiver-operated characteristic analysis. Results: Twenty-eight patients(63.6 %) were treated with antihypertensive drugs(HT group).The average changes frombaseline to operative BP were +13.9 +/- 13.9/8.4 +/- 8.7 mmHg(baseline BP:134.7 +/- 13.9/74.4 +/- 10.6 vs operative BP: 148.6 +/- 22.6/82.9 +/- 10.9, P < 0.05).Max BP was 152.8 +/- 23.4/83.5 +/- 11.5 mmHg.In 8 patients(18.2 %), systolic BP(SBP) reached 170mmHg(excessive riser). Operative and Max SBP were significantly correlated with baseline SBP (operative BP: r = 0.67, P < 0.01, Max BP: r = 0.70, P < 0.01) but not with age. The magnitude of the changes of SBP was not associated with baseline SBP. Max SBP in HT were significantly higher than non-HT (159.0 +/- 18.0 vs143.3 +/- 3.3, P < 0.01).In the subgroup of excessive riser, baseline SBP and increment SBP were significantly greater (151.1 +/- 13.0 vs130.7 +/- 14.9, P < 0.01 and +24.2 +/- 19.0 vs +11.4 +/- 15.1, P < 0.05, respectively). Multiple regression analyses indicated that Max SBP was significantly associated with baseline SBP ([latin sharp s] 1.05, P < 0.01). Pre SBP predicted excessive riser more accurately than Clinic SBP and the cut off values of that at maximum sensitivity (75.0 %) and specificity (78.8 %) was 144 mmHg. Conclusions: Baseline SBP can predict excessive SBP elevation during surgery. Patients whose preoperative SBP are more than 145 mmHg needscareful monitoring of BP during surgery and appropriate medication may be considered to prevent perioperative cardiovascular event.
    No preview · Article · Sep 2012 · Journal of Hypertension
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    ABSTRACT: Endothelium-derived hyperpolarizing factor (EDHF)-mediated hyperpolarization and relaxation, and endothelium-independent relaxations to the nitric oxide donor sodium nitroprusside and the adenosine 5'-triphosphate (ATP)-sensitive K(+)-channel opener levcromakalim were both impaired in mesenteric arteries of type II diabetic Goto-Kakizaki rats. The treatment with the superoxide dismutase mimetic tempol or its combination with the angiotensin II type 1 receptor blocker candesartan failed to improve EDHF-mediated responses, although both treatments partially improved endothelium-independent relaxations. These findings suggest that increased oxidative stress may in part account for the impaired endothelium-independent relaxations in diabetes, while it does not play a major role in the impaired EDHF-mediated responses.
    No preview · Article · Jul 2012 · Clinical and Experimental Hypertension
  • Yuko Ohta · Takuya Tsuchihashi · Kanako Kiyohara · Hideyuki Oniki
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    ABSTRACT: Blood pressure (BP) control in hypertensives has improved; however, it still remains to be insufficient. We have investigated the trend in BP control status of the hypertensive patients followed for 10 years in hypertension clinic. Subjects included 133 patients who have been followed from the first visit during 1998-2000 to the last visit during 2008-2010. During the mean follow-up period of 10.5 years, average BP and body weight significantly (P < .01) decreased from 143 ± 12/85 ± 8 mm Hg to 129 ± 14/68 ± 11 mm Hg, and from 59.8 ± 9.9 kg to 58.7 ± 10.6 kg, respectively. The achievement rate of good BP control defined as <140/90 mm Hg and the number of antihypertensive drugs also increased significantly during this period (39.1%-77.5% and 1.3 ± 1.0-2.2 ± 1.1, respectively, P < .01). Blood pressure control improved and the number of antihypertensive drugs also increased in 45 patients who were older than 65 years at the last visit. The use of Ca channel blockers (CCBs), angiotensin II receptor antagonists, and diuretics increased significantly during this period. Results suggest that lifestyle modification including body weight reduction as well as intensive antihypertensive treatment contributed to the improved BP control in hypertensive patients including the elderly.
    No preview · Article · May 2012 · Clinical and Experimental Hypertension
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    ABSTRACT: This study was designed to determine whether a high-salt diet would alter endothelial function and, if so, the relative contributions of endothelium-derived hyperpolarizing factor (EDHF) and nitric oxide (NO) to any changes in vasomotor responses. Male Dahl salt-sensitive (DS) rats were given either a high-salt diet (8% NaCl, DS-H) or a low-salt diet (0.4% NaCl, DS-L) for 6 weeks. Membrane potentials and contractile responses were recorded from the isolated superior mesenteric arteries. After salt loading, DS-H developed hypertension, while DS-L remained normotensive. No difference was found in acetylcholine (ACh)-induced, endothelium-dependent relaxation between the groups. However, after treatment with indomethacin and NO synthase inhibitor, EDHF-like relaxation was significantly greater in DS-H than in DS-L. In contrast, NO-mediated relaxation was significantly smaller in DS-Hthan in DS-L. Iberiotoxin (IbTx), a specific blocker of large-conductance calcium-dependent potassium (BKCa) channels, attenuated EDHF-like relaxation in DS-H but not in DS-L. IbTx marginally inhibited EDHF-mediated hyperpolarization only in DS-H. Endothelium-independent relaxation in response to sodium nitroprusside or levcromakalim was similar in both groups. In conclusion, EDHF-like relaxation is upregulated through the activation of BKCa channels in the mesenteric arteries of DS-H. As the overall relaxation in response to ACh did not differ between the groups, the upregulation of EDHF appears to compensate for the loss of NO in the mesenteric arteries of DS-H.
    No preview · Article · Apr 2012 · Hypertension Research
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    ABSTRACT: It has been shown that aging and hypertension are important risk factors to promote renal damage. However, little data are available on the effect of obesity on the progression of renal damage, especially in young and middle-aged individuals. The aim of this study was to determine the association between body mass index (BMI) and renal function evaluated by estimated glomerular filtration rate (eGFR) in Japanese men. We studied the cross-sectional association of BMI with eGFR in 3872 Japanese men in a work-site population (18-64 y; mean age 42.1 ± 0.2 y). Estimated glomerular filtration rate was calculated by a novel equation for Japanese men. Estimated glomerular filtration rate was negatively correlated with age, systolic blood pressure (SBP), hemoglobin A1c (HbA1c), and BMI. We performed multiple regression analysis, controlling for factors, such as SBP, low-density lipoprotein-cholesterol, gamma-glutamyl transpeptidase, age, HbA1c, and uric acid. The association between age and eGFR was highly statistically significant. In addition, BMI was still significantly associated with eGFR independently of SBP. Moreover, mean eGFR, which was adjusted for age, SBP, HbA1c, serum uric acid, and gamma-glutamyl transpeptidase, decreased from 88.9 mL/min/1.73 m(2) in the first quartile of BMI to 87.5 mL/min/1.73 m(2) in the second, 86.9 mL/min/1.73 m(2) in the third, and 85.9 mL/min/1.73 m(2) in the fourth quartile (test for trend, P < .0001). These results show that a close relationship is present between obesity and decreased eGFR in Japanese men. Keeping appropriate body weight, in addition to appropriate blood pressure, in young and middle age may be important to prevent renal damage in older age.
    No preview · Article · Oct 2011 · Clinical and Experimental Hypertension
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    Preview · Dataset · Jul 2011
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    ABSTRACT: To determine whether polymorphisms at codon 487 (*1, GAA=Glu; *2, AAA=Lys) of mitochondrial aldehyde dehydrogenase 2 (ALDH2) influence nitroglycerine (glyceryl trinitrate (GTN))-induced vasodilation, and whether GTN or isosorbide dinitrate (ISDN) is a more effective antianginal agent in each ALDH2 genotype. A randomised, open-label, crossover trial with 117 healthy Japanese (20-39 years) whose genotypes were determined (*1/*1, n=47; *1/*2, n=48; *2/*2, n=22) was performed at Kyushu University Hospital, Fukuoka, Japan. Participants were randomly assigned to treatment: sublingual spray of GTN (0.3 mg) or ISDN (1.25 mg). After ≥ 1 week, measurements were repeated using the other drug. The main outcome measures were the maximal rate of increase in the brachial artery diameter determined by ultrasonography, the time required to attain maximal dilation (T(max)) and the time required to attain 90% maximal dilation (T(0.9)). The maximal artery diameter increase in response to GTN or ISDN did not differ among genotypes. However, GTN T(max) was significantly longer for *2/*2 (299.7 s, 269.0-330.4) than *1/*1 (254.7 s, 238.6-273.4; p=0.0190). GTN T(0.9) was significantly longer in the *1/*2 (206.1 s, 191.7-219.3) and *2/*2 (231.4 s, 211.8-251.0) genotypes than *1/*1 (174.9 s, 161.5-188.3; p=0.0068, p<0.0001, respectively). In contrast, the time-course of ISDN-induced vasodilation did not differ among genotypes. GTN T(max) and T(0.9) among *1 allele carriers (*1/*1 and *1/*2) were significantly shorter than those of ISDN, whereas the time course of GTN and ISDN vasodilation did not differ among participants carrying *2/*2. The amplitude of GTN-induced vasodilation was not influenced by the ALDH2 genotype, but the response was significantly delayed in *2 allele carriers, especially *2/*2. GTN dilated the artery more quickly than ISDN in *1/*1 and *1/*2, but not in *2/*2. Trial registration number UMIN000001492 (UMIN-CTR database).
    Full-text · Article · Jul 2011 · BMJ Open
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    Preview · Dataset · Jul 2011
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    Preview · Dataset · Jul 2011
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    ABSTRACT: 1. Non-nitric oxide/prostaglandin-mediated endothelium-derived hyperpolarization (EDH) is considered to be mediated, in part, by gap junctions and it has been suggested that cAMP increases endothelium-derived hyperpolarizing factor (EDHF)-mediated relaxation through the modulation of gap junctions. Cilostamide, which inhibits phosphodiesterase III, has been suggested to augment EDHF-type relaxation by increasing the concentration of cAMP. 2. In the present study, we investigated the effect of cilostamide on EDH per se in mesenteric arteries of Wistar rats using a conventional microelectrode technique. 3. The resting membrane potential of the mesenteric arteries was significantly more negative in the presence of 10(-6) mol/L cilostamide compared with control conditions. Furthermore, EDH in response to 10(-6) mol/L acetylcholine (ACh) in the presence of 10(-5) mol/L indomethacin and 10(-4) mol/L N(G)-nitro-L-arginine was decreased in the presence of 10(-6) mol/L cilostamide by approximately 5 and 3.5 mV in proximal and distal arteries, respectively. 4. Glibenclamide (10(-5) mol/L), an ATP-sensitive potassium channel (K(ATP)) inhibitor, abolished the hyperpolarization to 10(-6) mol/L cilostamide. Furthermore, in the presence of glibenclamide, ACh-induced EDH was unaffected by cilostamide, suggesting that the inhibition of ACh-induced hyperpolarization by cilostamide in the absence of glibenclamide may be due to the smaller driving force for hyperpolarization because of the more negative membrane potential under such conditions. 5. The findings of the present study suggest that cilostamide produces hyperpolarization by activating K(ATP) channels, presumably by increasing cAMP. However, cilostamide alone may not directly affect EDH.
    No preview · Article · Feb 2009 · Clinical and Experimental Pharmacology and Physiology
  • Yasuo Kansui · Koji Fujii · Kenichi Goto · Hideyuki Oniki · Mitsuo Iida
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    ABSTRACT: 1. In the present study, we investigated the effects of chronic treatment of stroke-prone spontaneously hypertensive rats (SHRSP) with the statin fluvastatin on vascular Rho/Rho-kinase pathway mediated contraction, which has been shown to be upregulated in hypertension. 2. Contribution of the Rho/Rho-kinase pathway to noradrenaline-induced contraction of arteries from SHRSP was assessed by the inhibitory effect of Y-27632, a Rho/Rho-kinase inhibitor. Stroke-prone spontaneously hypertensive rats were treated with fluvastatin (10 mg/kg per day) for 1 month. 3. Treatment with fluvastatin tended to attenuate the contraction to noradrenaline and significantly decreased the Y-27632-sensitive component of the contraction in controls compared with fluvastatin-treated rats. 4. RhoA, as assessed by western blotting, was also reduced by fluvastatin treatment. 5. These findings suggest that chronic treatment with fluvastatin reduces the contractile response associated with Rho/Rho-kinase in arteries of hypertensive rats.
    No preview · Article · Sep 2006 · Clinical and Experimental Pharmacology and Physiology
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    ABSTRACT: The aim of the present study was to determine whether sex differences contribute to the association of serum uric acid and left ventricular hypertrophy in individuals with hypertension. Seventy participants with essential hypertension (34 men, 36 women; 54.4 +/- 1.6 years old) were enrolled to undergo echocardiography to calculate the left ventricular mass index (LVMI). Twenty-four-hour ambulatory blood pressure monitoring was done to assess blood pressure level precisely. The LVMI was significantly correlated with serum uric acid (r = 0.295, p = 0.013) in all participants. After controlling for factors such as age, sex, mean 24-h systolic blood pressure, creatinine clearance, and duration of hypertension, serum uric acid was still found to be significantly and independently associated with LVMI. Because serum uric acid was significantly higher in men than in women (6.8 +/- 0.3 and 5.1 +/- 0.2 mg/dl, respectively), subsequent analysis was performed by gender. Multiple regression analysis revealed that the LVMI was significantly and independently associated with serum uric acid in women, but not in men. The potential effect of uric acid on LV hypertrophy is more pronounced in female than in males with essential hypertension.
    Full-text · Article · Aug 2006 · Circulation Journal
  • Hideyuki Oniki · Koji Fujii · Yasuo Kansui · Kenichi Goto · Mitsuo Iida
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    ABSTRACT: Diabetes mellitus is an important risk factor for cardiovascular diseases, and vasodilator dysfunction may contribute to vascular complications in diabetes. We previously demonstrated that the angiotensin II receptor blocker (ARB) corrected the impaired endothelium-derived hyperpolarizing factor (EDHF)-mediated arterial hyperpolarization and relaxation associated with hypertension or aging, partially independently of blood pressure. To test whether EDHF-mediated, as well as endothelium-independent, relaxations would be altered in arteries from type II diabetic Goto-Kakizaki rats, and whether ARB would correct these alterations. Goto-Kakizaki rats were treated with either the ARB candesartan or a combination of hydralazine and hydrochlorothiazide for 8 weeks, beginning at 10 weeks of age. Membrane potentials and contractile responses were recorded from the isolated mesenteric arteries. The two treatments lowered blood pressure comparably. Acetylcholine-induced, EDHF-mediated hyperpolarization and relaxation in mesenteric arteries were markedly impaired in untreated Goto-Kakizaki rats compared with age-matched Wistar rats, and neither ARB nor the combination therapy improved these responses. On the other hand, relaxations to endothelium-derived nitric oxide, assessed in rings precontracted with high potassium solution, were similar among the four groups. Relaxation to the nitric oxide donor sodium nitroprusside and that to levcromakalim, an ATP-sensitive K-channel opener, were also impaired in untreated Goto-Kakizaki rats, and the response to sodium nitroprusside was partially improved in treated Goto-Kakizaki rats. These findings suggest that EDHF-mediated hyperpolarization and relaxation and endothelium-independent relaxations are both impaired in arteries of type II diabetic rats, and antihypertensive treatment with or without ARB partially corrects endothelium-independent relaxations to the nitric oxide donor but not EDHF-mediated responses.
    No preview · Article · Mar 2006 · Journal of Hypertension