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N Okuda

Publications and source records attributed to N Okuda.

At least 19 recordsLinked to original sources
PubMed2006

ED-71, a novel vitamin D analog, promotes bone formation and angiogenesis and inhibits bone resorption after bone marrow ablation.

ED-71, a novel analog of 1alpha,25-(OH)2 D3, increases bone mass to a greater extent than alfacalcidol, an 1alpha,25-(OH)2 D3 prodrug. In this study, we used a murine bone marrow ablation model to compare the effect of ED-71 on bone formation and resorption in vivo with that of 1alpha,25-(OH)2 D3. We discovered that bone matrix remodeling occurring within the first week after bone marrow ablation was enhanced by a single injection of ED-71, but not by 1alpha,25-(OH)2 D3. This enhancement was associated with an increase in bone surface. Trabecular bone resorption occurring from 1 to 2 weeks after the procedure was suppressed by a single injection of ED-71, but not 1alpha,25-(OH)2 D3, with treated mice exhibiting a reduction in osteoclast numbers, despite increases in osteoblast surface. As seen with the single injection, daily administration of ED-71 also enhanced bone modeling. Bone marrow osteoblast differentiation was also augmented by ED-71 pretreatment. Furthermore, ED-71 treatment immediately after bone marrow ablation enhanced angiogenesis within the bone marrow cavity via enhancement of VEGF(120) expression. In this paper, we clearly demonstrate that ED-71 is an orally administered small molecular weight compound with an anabolic effect on bone metabolism.

Animals↗
PubMed2003

INTERMAP: the dietary data--process and quality control.

The aim of this report is to describe INTERMAP standardized procedures for assessing dietary intake of 4680 individuals from 17 population samples in China, Japan, UK and USA: Based on a common Protocol and Manuals of Operations, standardized collection by centrally trained certified staff of four 24 h dietary recalls, two timed 24-h urines, two 7-day histories of daily alcohol intake per participant; tape recording of all dietary interviews, and use of multiple methods for ongoing quality control of dietary data collection and processing (local, national, and international); one central laboratory for urine analyses; review, update, expansion of available databases for four countries to produce comparable data on 76 nutrients for all reported foods; use of these databases at international coordinating centres to compute nutrient composition. Chinese participants reported 2257 foods; Japanese, 2931; and UK, 3963. In US, use was made of 17,000 food items in the online automated Nutrition Data System. Average time/recall ranged from 22 min for China to 31 min for UK. Among indicators of dietary data quality, coding error rates (from recoding 10% random samples of recalls) were 2.3% for China, 1.4% for Japan, and UK; an analogous US procedure (re-entry of recalls into computer from tape recordings) also yielded low discrepancy rates. Average scores on assessment of taped dietary interviews were high, 40.4 (Japan) to 45.3 (China) (highest possible score: 48); correlations between urinary and dietary nutrient values--similar for men and women--were, for all 4680 participants, 0.51 for total protein, range across countries 0.40-0.52; 0.55 for potassium, range 0.30-0.58; 0.42 for sodium, range 0.33-0.46. The updated dietary databases are valuable international resources. Dietary quality control procedures yielded data generally indicative of high quality performance in the four countries. These procedures were time consuming. Ongoing recoding of random samples of recalls is deemed essential. Use of tape recorded dietary interviews contributed to quality control, despite feasibility problems, deemed remediable by protocol modification. For quality assessment, use of correlation data on dietary and urinary nutrient values yielded meaningful findings, including evidence of special difficulties in assessing sodium intake by dietary methods.

Adult↗
PubMed2003

Nutrient intakes of middle-aged men and women in China, Japan, United Kingdom, and United States in the late 1990s: the INTERMAP study.

The purpose of the study was to compare nutrient intakes among Chinese, Japanese, UK, and US INTERMAP samples, and assess possible relationships of dietary patterns to differential patterns of cardiovascular diseases between East Asian and Western countries. Based on a common Protocol and Manuals of Operations, high-quality dietary data were collected by four standardized 24-h dietary recalls and two 24-h urine collections from 17 population samples in China (three samples), Japan (four samples), UK (two samples), and USA (eight samples). There were about 260 men and women aged 40-59 years per sample--total N=4680. Quality of dietary interview and data entry were monitored and enhanced by extensive systematic ongoing quality control procedures at local, country, and international level. Four databases on nutrient composition of foods from the four countries were updated and enhanced (76 nutrients for all four countries) by the Nutrition Coordinating Center, University of Minnesota, in cooperation with Country Nutritionists. The mean body mass index was much higher for Western than East Asian samples. Macronutrient intakes differed markedly across these samples, with Western diet higher in total fat, saturated and trans fatty acids, and Keys dietary lipid score, lower in total carbohydrate and starch, higher in sugars. Based on extensive published data, it is a reasonable inference that this pattern relates to higher average levels of serum total cholesterol and higher mortality from coronary heart disease in Western than East Asian populations. The rural Chinese diet was lower in protein, especially animal protein, in calcium, phosphorus, selenium, and vitamin A. Dietary sodium was higher, potassium lower, hence Na/K ratio was higher in the Asian diet, especially for Chinese samples. This pattern is known to relate to risks of adverse blood pressure level and stroke. At the end of the 20th century, East Asian and Western diets remain significantly different in macro- and micronutrient composition. Both dietary patterns have aspects that can be regarded, respectively, as adverse and protective in relation to the major adult cardiovascular diseases. In both Asian and Western countries, public efforts should be targeted at overcoming adverse aspects and maintaining protective patterns for prevention and control of cardiovascular diseases.

Adult↗
PubMed2003

Differences in cardiovascular disease risk factors between Japanese in Japan and Japanese-Americans in Hawaii: the INTERLIPID study.

Despite increase in serum total cholesterol, high smoking rate, and frequency of adverse blood pressure levels in Japan, coronary heart disease (CHD) incidence and mortality apparently remain substantially lower at all ages in Japan than in the US and other Western societies. To better understand these differences, we compared CHD biomedical risk factors and dietary variables in Japanese living in Japan and 3rd and 4th generation Japanese emigrants living a primarily Western lifestyle in Hawaii, in an ancillary study of the INTERMAP. Men and women aged 40-59 years were examined by common standardized methods-four samples in Japan (574 men, 571 women) and a Japanese-American sample in Hawaii (136 men, 131 women). Average systolic (SBP) and diastolic (DBP) blood pressures were significantly higher in men in Japan than in Hawaii; there were no significant differences in women. The treatment rate of hypertension was much lower in Japan than Hawaii. Smoking prevalence was higher, markedly so for men, in Japan than Hawaii. Body mass index, serum total and low-density lipoprotein cholesterol, HbA1c, and fibrinogen were significantly lower in Japan than in Hawaii; high-density lipoprotein cholesterol was higher in Japan. Total fat, saturated fatty acid intake, and Keys dietary lipid score were lower in Japan than in Hawaii. Polyunsaturated/saturated fatty acid ratio and omega-3 fatty acid intake were higher in Japan than in Hawaii. In conclusion, levels of several, especially lipid, CHD risk factors were generally lower in Japanese in Japan than in Japanese in Hawaii. These differences were smaller for women than men between Japan and Hawaii. They may partly explain lower CHD incidence and mortality in Japan than Western industrialized countries.

Adult↗
PubMed2003

Higher blood pressure in middle-aged American adults with less education-role of multiple dietary factors: the INTERMAP study.

Extensive evidence exists that an inverse relation between education and blood pressure prevails in many adult populations, but little research has been carried out on reasons for this finding. A prior goal of the INTERMAP Study was to investigate this phenomenon further, and to assess the role of dietary factors in accounting for it. Of the 4680 men and women aged 40-59 years, from 17 diverse population samples in Japan, People's Republic of China, UK, and USA, a strong significant inverse education-BP relation was manifest particularly for the 2195 USA participants, independent of ethnicity. With participants stratified by years of education, and assessment of 100+ dietary variables from four 24-h dietary recalls and two 24-h urine collections/person, graded relationships were found between education and intake of many macro- and micronutrients, electrolytes, fibre, and body mass index (BMI). In multiple linear regression analyses with systolic BP (SBP) and diastolic BP (DBP) of individuals the dependent variables (controlled for ethnicity, other possible nondietary confounders), BMI markedly reduced size of education-BP relations, more so for women than for men. Several nutrients considered singly further decreased size of this association by > or =10%: urinary 24-h Na and K excretion, Keys dietary lipid score, vegetable protein, fibre, vitamins C and B6, thiamin, riboflavin, folate, calcium, magnesium, and iron. Combinations of these dietary variables and BMI attenuated the education-SBP inverse coefficient by 54-58%, and the education-DBP inverse coefficient by 59-67%, with over half these effects attributable to specific nutrients (independent of BMI). As a result, the inverse education-BP coefficients ceased to be statistically significant. Multiple specific dietary factors together with body mass largely account for the more adverse BP levels of less educated than more educated Americans. Special efforts to improve eating patterns of less educated strata can contribute importantly to overcoming this and related health disparities in the population.

Adult↗
PubMed2001

Cause of residual hypertension after adrenalectomy in patients with primary aldosteronism.

The cause of residual hypertension after adrenalectomy for primary aldosteronism (PA) is unknown. The purpose of this study is to investigate the characteristic pathological kidney features associated with PA. Between 1977 and 1999 at our hospital, 26 patients with PA caused by a unilateral adrenal cortical adenoma (Conn's syndrome) underwent unilateral adrenalectomy with concurrent open-wedge renal biopsy. Patients were categorized into two groups: (1) those with normotension with diastolic blood pressure less than 90 mm Hg who were not administered antihypertensive drugs, and (2) those with residual hypertension with diastolic blood pressure of 90 mm Hg or greater who were administered medication for 6 months after surgery. Thirteen patients were cured of hypertension postoperatively, and 12 patients were administered antihypertensive medications. Glomerulosclerosis, renal arteriolosclerosis, and preoperative left ventricular mass (LVM) index were worse in the group with residual hypertension than in that with normotension (17.8% +/- 7.8% versus 9.6% +/- 3.8%; P = 0.01; 2.5 +/- 0.5 versus 1.6 +/- 0.4, Bader's grade; P = 0.005; and 165 +/- 31 versus 139 +/- 24 g/m(2); P = 0.02, respectively). Severity of tubulointerstitial injury, preoperative duration of hypertension, preoperative severity of proteinuria, plasma aldosterone level, and serum potassium concentration were not significantly different between the two groups. In conclusion, severity of glomerulosclerosis and arteriolosclerosis and LVM are related to blood pressure after adrenalectomy in patients with PA.

Adenoma↗
PubMed2001

Intravascular ultrasound imaging before and after angioplasty for stenosis of arteriovenous fistulae in haemodialysis patients.

BACKGROUND: Complications of haemodialysis vascular access have emerged as a major cause of patient morbidity. Intravascular ultrasound imaging is a new technical modality providing visualization of the vessel lumen and wall structure in a cross-sectional fashion. Percutaneous transluminal angioplasty has long been used in the treatment of stenoses of arteriovenous fistulae. However, there is no detailed quantitative information on the stenotic lesion and the morphological change by angioplasty. METHODS: Intravascular ultrasound studies were performed in 40 haemodialysis patients with 63 stenoses in arteriovenous fistulae who had percutaneous transluminal angioplasty. The patients were qualitatively and quantitatively evaluated for echogenic patterns and morphological changes before and after angioplasty. RESULTS: Morphological plaque features in stenotic lesions were classified as 37 soft (58%), five hard (8%), 20 mixed (32%), and one calcified sites. Plaque fractures after angioplasty were detected in 45/63 (71%) instances. The lumen cross-sectional area was found to be dilated approximately threefold (from 3.8+/-2.4 to 11.1+/-4.5 mm(2)) and the external elastic membrane cross-sectional area was dilated approximately twofold (from 11.1+/-5.3 to 19.8+/-8.1 mm(2)) after angioplasty. CONCLUSION: These results indicate that intravascular ultrasound allows both qualitative and quantitative assessments of arteriovenous fistulae in haemodialysis patients. The results further suggest that the mechanism of expansion of arteriovenous fistulae stenoses by percutaneous transluminal angioplasty involves stretching of the vessel wall as well as plaque fractures.

Adult↗
PubMed2000

Intermittent light irradiation with second- or hour-scale periods controls anthocyanin production by strawberry cells*

Anthocyanin production by strawberry cells depends not only on light intensity but also on the light/dark cycle operation with hour- or second-scale periods. These findings are useful for designing and operating photobioreactors for enhanced anthocyanin production. Intermittent illumination with a second-scale period produces the same amount of anthocyanin as continuous light, suggesting that the light intensity distribution within a photobioreactor does not cause suppressed production. In the hour-scale cycle, continuous light operation enhanced anthocyanin production more than the light/dark cycle process.

Journal Article↗
PubMed2000

Effects of a low-energy diet and an insulin-sensitizing agent on ambulatory blood pressure in overweight hypertensive patients.

OBJECTIVE: To clarify the role of insulin resistance and hyperinsulinaemia in the pathogenesis of obesity-related hypertension. DESIGN: An open study comparing the effects of weight reduction by low-energy diet and treatment with troglitazone, an insulin-sensitizing agent. SETTING: A tertiary teaching hospital. PATIENTS: Thirty overweight hypertensive patients (15 men and 15 women, mean age 61 years, mean body mass index 29.1 kg/m2). INTERVENTIONS: Fifteen patients were assigned to a weight-reduction programme by low-energy diet (3360 kJ/day) for 3 weeks; the remaining 15 patients were treated with troglitazone (400 mg/day) for 8 weeks. MAIN OUTCOME MEASURES: Casual and ambulatory blood pressures, glucose and lipid metabolism, and insulin sensitivity. RESULTS: The baseline values of body mass index, fasting and post-glucose plasma insulin, and casual and ambulatory blood pressures were comparable between the two groups. Weight reduction (4.1 +/- 0.3 kg, mean +/- SEM) was associated with significant decreases in plasma insulin, blood glucose, homeostasis model assessment (HOMA) insulin resistance index, serum triglyceride, casual blood pressure (7.7 +/- 2.3/ 3.9 +/- 1.4 mmHg) and 24 h blood pressure (8.3 +/- 1.9/ 4.3 +/- 1.1 mmHg). Treatment with troglitazone caused comparable decreases in the metabolic parameters and HOMA index, but did not change casual or 24 h blood pressure (0.8 +/- 3.4/0.8 +/- 2.1 and 1.5 +/- 2.4/ 1.0 +/- 1.9 mmHg, respectively). CONCLUSIONS: Insulin resistance/hyperinsulinaemia may not have an important role in the pathogenesis of obesity-related hypertension. The antihypertensive effect of weight reduction seems to be mediated mainly by other mechanisms.

Adult↗
PubMed2000

Effects of diltiazem retard on ambulatory blood pressure and heart rate variability in patients with essential hypertension.

BACKGROUND: Dihydropyridine calcium antagonists increase heart rate due to reflex activation of the sympathetic nervous system, although these effects are less obvious for long-acting agents. OBJECTIVE: To study the effects of diltiazem retard, a long-acting nondihydropyridine calcium antagonist, on 24h blood pressure, heart rate and autonomic nerve activity in patients with essential hypertension. DESIGN: Randomized crossover design. METHODS: Thirteen patients [five men and eight women, aged 64+/-2 years (mean+/-SEM)] were administered placebo or diltiazem retard (100-200mg once daily) for 4 weeks each. Ambulatory monitoring of blood pressure and heart rate, and electrocardiography were carried out at the end of each period using a multibiomedical recorder (TM-2425). Autonomic nerve activity was evaluated by power spectral analysis of variability of heart rate using the high-frequency component as an index of parasympathetic nerve activity and the ratio of the low-frequency component and the high-frequency component as an index of sympathovagal balance. RESULTS: Treatment with diltiazem retard significantly decreased 24h average blood pressure and heart rate by 11.6+/-3.6/5.7+/-1.8mmHg and 5.0+/-1.1 beats/min, respectively. The changes in daytime and night-time values were comparable. Diltiazem retard also significantly decreased daytime and 24h low:high-frequency-component ratio (2.0+/-0.2 versus 1.7+/-0.2 and 1. 8+/-0.2 versus 1.6+/-0.2, respectively). CONCLUSIONS: These results indicate that diltiazem retard is effective as a once-daily antihypertensive agent and has favorable effects on heart rate and the autonomic nervous system.

Aged↗
PubMed2000

[Phosphate kinetics in patients on chronic hemodialysis].

To investigate the phosphate kinetics in hemodialysis (HD), 8 patients in a stable condition, who were receiving HD three times a week for 4 hours per session, were investigated. Plasma phosphate was under 7 mg/dl, and residual renal function had almost disappeared. Dialysate containing phosphate was prepared by adding Na2HPO4 using a micro-infusion pump from the inlet of single pass dialysate in the individual dialysate delivery system. In the first week, Na2HPO4 was not added as the control period. In the second session of the second and third week, Na2HPO4 was added to give a phosphate concentration of 1.0 and 2.0 mmol/l in the dialysate, respectively. Total phosphate mass removal was 777 +/- 46.64 mg in the control period, 403 +/- 67.21 mg in the second week, and -230 +/- 214.8 mg in the third week. Total phosphate mass removal in the second and third week was significantly lower than that of the control period. Plasma phosphate concentration was significantly decreased after the HD compared with before the HD in the control and second week. There was no significant difference in plasma phosphate concentration between the period before HD and at 48 hours in the control and the second week. Plasma phosphate concentration before HD not only depended on phosphate mass removal by HD, but also on other factors. We suggest that dialysate containing phosphate might prevent excessive phosphate removal from non-extracellular compartments during HD.

Adult↗
PubMed1999

Female mating strategy and male brood cannibalism in a sand-dwelling cardinalfish.

I investigated male and female sexual strategies of a cardinalfish, Apogon niger, which breeds in sandy areas at sporadic coral colonies. Males mouthbrood an egg mass received from one female at a time. Because of the lengthy mouthbrooding period, the interspawning interval was shorter for females than for males. Females moved between coral colonies to find mates more extensively than did males, and more frequently deserted mates after spawning. The females shortened their interspawning intervals by changing mates, especially in the late breeding season, when their mobility was highest. Their mobility was positively correlated with their disappearance rate, suggesting that mate search increases mortality. This may reduce competition between females for males, resulting in an unbiased rather than female-biased operational sex ratio. Males, on the other hand, practised filial cannibalism of entire broods, which might allow them partially to compensate for the lack of food during the mouthbrooding period. The reproductive loss entailed by filial cannibalism could be effectively offset if males remate soon afterwards. However, cannibal males took a long time to remate because few females were available. Filial cannibalism was less frequent than in a boulder-dwelling congener in which males have easy access to mates. Low mate availability may inhibit male A. niger from committing filial cannibalism. Copyright 1999 The Association for the Study of Animal Behaviour.

Journal Article↗
PubMed1999

Etidronate (EHDP) inhibits osteoclastic-bone resorption, promotes apoptosis and disrupts actin rings in isolate-mature osteoclasts.

Bisphosphonates, therapeutic reagents against tumoral bone diseases (Paget's disease or osteoporosis), are potent inhibitors of bone resorption. The mechanisms by which they directly act on mature osteoclasts remain unclear. Using a recently developed technique for isolation of highly purified mammalian mature osteoclasts, we demonstrated that etidronate [ethane-1-hydroxy-1,1-diphosphonate (EHDP), 1-hydroxy-1,1-ethylidenebisphosphonate], inhibited directly osteoclastic bone-resorbing activity by pit assay. In addition, EHDP also directly induced apoptosis and disrupted actin rings in osteoclasts. The data support previous data on non-purified osteoclasts and results in vivo.

Actins↗
PubMed1999

Effect of propranolol on central neurotransmitter release in Wistar rats analysed by brain microdialysis.

1. The effect of propranolol on amino acid neurotransmitter release in the rostral ventrolateral medulla (RVLM) was examined in urethane-anaesthetized male Wistar rats. 2. Amino acids released in the RVLM in response to intravenous administration of propranolol (0.4 mg/kg per min; n = 6) or nitroglycerin (0.02 mg/kg per min; n = 5) were determined by the brain microdialysis method. 3. Amino acids in dialysates were analysed by high-performance liquid chromatography and were quantified by ultraviolet absorbance. 4. Administration of both intravenous propranolol and nitroglycerin significantly decreased arterial blood pressure. Heart rate was decreased only by propranolol. 5. The reduction in arterial blood pressure produced by intravenous propranolol was accompanied by a decrease in the release of the excitatory amino acid glutamate in the RVLM. 6. The reduction in arterial blood pressure following intravenous nitroglycerin was not accompanied by a release of glutamate. 7. There were no significant changes in the levels of other amino acids (glycine, taurine, GABA) following either propranolol or nitroglycerin. 8. The decrease in glutamate release in the RVLM may account, in part, for the central depressor mechanism of propranolol.

Adrenergic beta-Antagonists↗
PubMed1999

Autonomic function in hypertensive patients with neurovascular compression of the ventrolateral medulla oblongata.

OBJECTIVE: To study whether abnormalities of autonomic function exist in patients with essential hypertension and neurovascular compression (NVC) of the medulla oblongata. SUBJECTS AND METHODS: We studied 25 untreated patients with essential hypertension (13 men and 12 women, 27-74 years old). High-resolution magnetic resonance imaging and magnetic resonance angiography were used to detect NVC. Twenty-four-hour ambulatory monitoring of blood pressure and electrocardiogram were performed, and the power spectrum of heart rate variability was analyzed. On a separate day, various autonomic activity tests, including mental stress, hand grip, cold pressor, and Valsalva maneuver were performed. Baroreflex sensitivity was calculated from changes of blood pressure and R-R interval during phenylephrine infusion. A clonidine suppression test was also performed, with measurement of plasma catecholamine levels. RESULTS: Fourteen of 25 patients (56%) had NVC (C group), and 11 patients did not have NVC (NC group). There were no significant differences in age, sex, family history, or duration of hypertension between the C and NC groups. Average 24-h systolic blood pressure was similar between the two groups, although 24-h diastolic blood pressure was higher in the C group than the NC group. Daytime, night-time, and 24-h heart rate was significantly higher in the C group than in the NC group. Night-time low frequency/high frequency ratio was slightly higher in the C group. Plasma norepinephrine levels were significantly higher (467 +/- 217 versus 299 +/- 122 pg/ml), and baroflex sensitivity was slightly lower in the C group than in the NC group. Responses of blood pressure and heart rate to mental stress, cold pressor, hand grip, Valsalva maneuver, phenylephrine infusion, and clonidine tests were not significantly different between the two groups. CONCLUSIONS: NVC of the medulla oblongata was frequently found in patients with essential hypertension. Patients with NVC appeared to have enhanced sympathetic nervous activity compared with those without the compression.

Adult↗
PubMed1999

Epidemic of gastrointestinal tract infection including hemorrhagic colitis attributable to Shiga toxin 1-producing Escherichia coli O118:H2 at a junior high school in Japan.

BACKGROUND: An epidemic of gastrointestinal disturbances related to food ingestion occurred at a junior high school in Komatsu, Japan, and was caused by specifically Shiga toxin (Stx) 1-producing Escherichia coli O118:H2, which has not been reported previously in humans. No outbreak of E coli-producing Stx 1 alone had occurred. METHODS: A total of 526 students and 35 adult staff members who ate the same food at lunch in the school were investigated. Questionnaires about food consumption at lunch were given to all 561 subjects as well as to clinics and hospitals that had treated 79 patients. Stool specimens from 525 subjects, and food, water, and environmental specimens, including cooking utensils, were collected in an attempt to identify the pathogen. RESULTS: A total of 126 subjects (22.5%) developed a diarrheal illness. The pathogen was isolated from the stool in 131 subjects, 49 of which were asymptomatic, and from a dipper. Salads served over several days were identified as high-risk from food analysis. Gastrointestinal symptoms resembled those associated with previous infections of Stx-producing E coli, but were mild. No cases of the hemolytic-uremic syndrome developed. Headache was present in 87 patients. Three patients underwent surgery for acute appendicitis during this epidemic. Four of five carriers had received an antibiotic effective against the pathogen. CONCLUSIONS: This outbreak of E coli O118:H2 demonstrated the clinical and epidemiologic features of infection by E coli that produces Stx 1 alone. Infections with such organisms are being recognized increasingly, and the pattern of disease observed may differ from the pattern observed with E coli O157:H7.

Acute Disease↗
PubMed1998

Patch clamp studies on ion pumps of the cytoplasmic membrane of Escherichia coli. Formation, preparation, and utilization of giant vacuole-like structures consisting of everted cytoplasmic membrane.

Formation of giant protoplasts from normal Escherichia coli cells resulted in the formation of giant vacuole-type structures (which we designate as provacuoles) in the protoplasts. Electron microscopic observation revealed that these provacuoles were surrounded by a single membrane. We detected inner (cytoplasmic) membrane proteins in the provacuolar membrane but not outer membrane proteins. Biochemical analyses revealed that the provacuoles consist of everted cytoplasmic membranes. We applied the patch clamp method to the giant provacuoles. We have succeeded in measuring current that represents inward movement of H+ because of respiration and to ATP hydrolysis by the FoF1-ATPase. Such current was inhibited by inhibitors of the respiratory chain or FoF1-ATPase. This method is applicable for analyses of ion channels, ion pumps, or ion transporters in E. coli or other microorganisms.

Cytoplasm↗