Evaluation of velopharyngeal function using high-speed cine-magnetic resonance imaging based on T2-weighted sequences: a preliminary study

The objective was to introduce a new technique for visualizing the three-dimensional (3D) movements of velopharyngeal-related muscles using high-speed cine-magnetic resonance imaging (MRI) based on T2-weighted sequences. The evaluation of phonation- and water swallowing-related events was performed in 11 healthy subjects. Specifically, whether cine-MRI could precisely visualize normal velopharyngeal function during these two events was examined. The 3D movements of the soft palate, superior pharyngeal constrictor muscles, and levator veli palatini muscles were visualized in all 11 subjects. A noteworthy finding was that the magnetic resonance signals of the superior constrictor pharyngeal muscles and the levator veli palatini muscles were significantly higher during phonation and during water swallowing than at rest. This initial study suggests that the 3D movements of velopharyngeal-related muscles can be successfully and precisely visualized without side effects. The magnetic resonance signal changes seen in the superior pharyngeal constrictor and levator veli palatini muscles using the technique described here should be useful to develop better methods of evaluation of velopharyngeal function.

Alterations in 18F-FDG accumulation into neck-related muscles after neck dissection for patients with oral cancers

BACKGROUND

18F-fluoro-2-deoxy-D-glucose (18F-FDG) accumulations are commonly seen in the neck-related muscles of the surgical and non-surgical sides after surgery with neck dissection (ND) for oral cancers, which leads to radiologists having difficulty in diagnosing the lesions. To examine the alterations in 18F-FDG accumulation in neck-related muscles of patients after ND for oral cancer.

MATERIAL AND METHODS

18F-FDG accumulations on positron emission tomography (PET)-computed tomography (CT) in neck-related muscles were retrospectively analyzed after surgical dissection of cervical lymph nodes in oral cancers.

RESULTS

According to the extent of ND of cervical lymph nodes, the rate of patients with 18F-FDG-PET-positive areas increased in the trapezius, sternocleidomastoid, and posterior neck muscles of the surgical and/or non-surgical sides. In addition, SUVmax of 18F-FDG-PET-positive areas in the trapezius and sternocleidomastoid muscles were increased according to the extent of the ND.

CONCLUSIONS

In evaluating 18F-FDG accumulations after ND for oral cancers, we should pay attention to the 18F-FDG distributions in neck-related muscles including the non-surgical side as false-positive findings.

Intraoperative detection of viable bone with fluorescence imaging using Visually Enhanced Lesion Scope in patients with bisphosphonate-related osteonecrosis of the jaw: clinical and pathological evaluation

There is no standard surgical protocol of bisphosphonate-related osteonecrosis of the jaws (BRONJ), because of the impossibility to visualize this feature intraoperatively. The aim of this study was to introduce how to provide preoperative labeling of the viable bone with minocycline bone fluorescence technique (MBFT) by using VELscope® and investigate histopathologically.

INTRODUCTION

The American Association of Oral and Maxillofacial Surgeons (AAOMS) and the Japanese Society of Oral and Maxillofacial Surgeons (JSOMS) now recommend a more conservative treatment strategy. There is no standard surgical protocol of bisphosphonate-related osteonecrosis of the jaws (BRONJ) because of the impossibility to visualize this feature intraoperatively. The aim of this study was to introduce a mechanism providing preoperative labeling of a viable bone using minocycline bone fluorescence technique (MBFT) with VELscope® and to histopathologically investigate.

METHODS

This report describes a surgical technique used in six patients with BRONJ who underwent jawbone resection under minocycline bone fluorescence imaging using VELscope®. Subsequently, we investigated and compared the clinical findings using VELscope® and histopathological findings.

RESULTS

Histopathological examinations showed that the non-fluorescent moiety was consistent with the BRONJ lesions.

CONCLUSIONS

The surgical treatments that were exactly performed using MBFT with VELscope® offered successful management of BRONJ. This bone fluorescence helped to define the margins of resection, thus improving surgical therapy for extended osteonecrosis.

Effects of a slow-release nifedipine on 24-hour ambulatory blood pressure and ischemic changes on 24-hour ambulatory electrocardiogram in patients with severe coronary artery disease

Calcium antagonists have long been used as first-line drugs for hypertension and angina. However, deleterious effects have also been reported in patients treated with calcium antagonists. Thus, we evaluated the effect of a slow-release twice-daily formulation of nifedipine in 10 patients with severe coronary artery disease. Twenty-four-hour ambulatory electrocardiography (AECG) and blood pressure monitoring (ABPM) were performed simultaneously to detect any association between ischemic episodes on the ECG and changes in blood pressure (BP) and heart rate with and without nifedipine. Increased oxygen demand due to an increased systolic BP and heart rate was associated with ischemic episodes without nifedipine, while those with nifedipine were accompanied by a fall in diastolic BP and a rapid increase in heart rate. This slow-release twice-daily formulation of nifedipine may induce myocardial ischemia through a heart-rate increase and a decrease in coronary blood flow due to lower diastolic BP in patients with severe coronary artery disease. A once-daily formulation of nifedipine might be of great value for such patients.

A case of hyperreninemic hypertension after extracorporeal shock-wave lithotripsy

A 53-year-old male was found to have hypertension caused by the significant secretion of renin from an atrophic left kidney. He had undergone extracorporeal shock-wave lithotripsy (ESWL) for left renal lithiasis 11 years previously. A renal dynamic study with 99mTc-diethylenetriaminepentaacetic acid (DTPA) indicated that the rate of renal excretion and uptake was decreased in the left kidney and normal in the right kidney. Renal angiography demonstrated a normal right renal artery and a small but nonstenotic left renal artery. The ratio of PRA in the left renal vein to that in the right renal vein was 1.7. Blood pressure could be lowered to the range of 140-150/80-90 mmHg with imidapril, an ACE inhibitor. ESWL may cause hypertension via the well-known Page kidney effect. In this case, the kidney, atrophic probably due to ESWL, released a significant amount of renin.

Roles of renal dopamine and kallikrein-kinin systems in antihypertensive mechanisms of exercise in rats

We have previously shown that both renal dopamine (DA) and kallikrein-kinin systems are activated by exercise in mild hypertensives. We aimed to confirm the effects of exercise on the renal DA system and the stimulatory effects of DA on the renal kallikrein-kinin system in rats. In experiment 1, 12 male Dahl salt-sensitive (DS) rats given a 4% salt diet were divided into two groups. Rats in the exercise group were forced to run at 8 m/min, 60 min/day, 5 days/week for 4 weeks. Daily urinary volume, urinary excretion of sodium, free DA, and kallikrein activity were measured weekly. Renal aromatic-L-amino-acid decarboxylase (AADC) activities were assayed at the end of the experiment. In experiment 2, 15 male Sprague-Dawley (SD) rats were randomly divided into 3 groups, a DA-5 (5 microg of DA/kg/min), a DA-10 (10 microg of DA/kg/min), and a control group. DA or vehicle was administered subcutaneously with an osmotic pump for 2 weeks. Daily urinary volume, urinary excretion of sodium, aldosterone, DA, and kallikrein activity were measured weekly. Plasma renin activity, aldosterone concentration, and renal kallikrein mRNA levels were determined at the end of the experiment. In experiment 1, urinary excretion of free DA and renal AADC activities in the exercise group were significantly higher than those in the non-exercise group at week 4. In experiment 2, renal kallikrein mRNA levels and urinary volume were significantly increased in the DA-10 group compared to the control group, although there were no differences in urinary kallikrein activities. Plasma aldosterone concentration was significantly decreased in the DA-10 group compared to that in the control group despite a lack of differences in plasma renin activities. In conclusion, exercise increased the urinary excretion of free DA, probably through increased renal AADC activity in DS rats. DA amplified renal kallikrein mRNA levels and decreased plasma aldosterone levels, probably through its suppression of aldosterone in the adrenal glands. Activation of the kallikrein-kinin system might be counteracted by post-transcriptional modification of aldosterone. These results suggest that exercise enhances renal dopamine production by activating renal AADC activity, which in turn stimulates the renal kallikrein-kinin system.

The regression of left ventricular hypertrophy by imidapril and the reduction of serum procollagen type III amino-terminal peptide in hypertensive patients

Angiotensin-converting enzyme (ACE) inhibitors are known to be the most effective antihypertensive drugs for reducing left ventricular mass in hypertensives when compared to other classes of drugs. In the present study, we evaluated the effects of imidapril, an ACE inhibitor, on serum procollagen type III amino-terminal peptide (PIIIP) levels as well as the left ventricular mass index (LVMI). The subjects consisted of 15 patients (12 men and 3 women) in the outpatient clinic of our hospital who were diagnosed as essential hypertensives and who had not been treated with any antihypertensive medication prior to the study. Left ventricular hypertrophy was observed in all of the patients, ie., LVMI >110 g/m2 in men and >106 g/m2 in women. Blood pressure, LVMI, and serum PIIIP levels were measured before and after treatment with imidapril for 6 months. The starting dose of imidapril was 5 mg, and this was increased to 10 mg. Finally, 1 mg of trichlormethiazide was added to obtain adequate control of blood pressure. Blood pressure significantly decreased in 12 patients, and the mean LVMI decreased significantly from 153.1 +/- 9.0 to 135.4 +/- 6.3 (p< 0.01) after treatment. The changes in LVMI and PIIIP levels with treatment had significant correlation (r=0.639, p< 0.05). The present study showed that imidapril reduces the left ventricular mass in hypertensives after 6 months of treatment, and that this may at least in part be due to a decrease in the collagen content of the hypertrophied heart, suggesting that serum PIIIP levels are a useful marker of the regression of left ventricular hypertrophy.

Increased chymase activity in internal thoracic artery of patients with hypercholesterolemia

Apart from ACE, various angiotensin II (Ang II)-forming serine proteinases (eg, chymase, kallikrein, and cathepsin G) are known to exist in human tissues, but their clinical significance or the regulatory mechanisms that control their activities are not well established. A recent clinical study has shown that chymase activity was significantly increased in human atherosclerotic or aneurysmal aorta. The association between vascular Ang II-forming activities (AIIFAs) in the human internal thoracic artery (ITA) and various clinical parameters was studied with the use of ITAs obtained from 32 patients who underwent coronary artery bypass graft surgery. Total and ACE- and chymase-dependent AIIFAs in homogenates of ITAs were determined. Total AIIFA was 8.67+/-0.86 (nmol Ang II formed. min(-1). mg protein(-1) [U]), and approximately 95% of the activities were due to chymase. Serum total cholesterol level, but no other risk factors, significantly correlated with chymase- (r=0. 60, P<0.001) and ACE- (r=0.35, P<0.05) dependent AIIFAs, respectively. LDL cholesterol level was also correlated with chymase-dependent AIIFAs (r=0.47, P<0.05). Mast cells identified through the use of toluidine blue or immunohistochemical staining appeared in the adventitia but not in the intima or media of ITAs. Our results suggest that an increased plasma LDL cholesterol level may induce increased arterial chymase and ACE activity.

Structure of a kallikrein-like enzyme and its tissue localization in the dog

We previously purified a kallikrein-like enzyme from the dog heart and demonstrated that it is not only able to form kinins but can also convert angiotensin (Ang) I to Ang II. The aim of the present study was to clarify the structure and tissue localization of this enzyme. Western blot analysis of various canine tissues was performed with antiserum against the purified dog heart enzyme. The purified enzyme was subjected to a determination of its amino acid composition and a sequence analysis. Western blotting indicated that this enzyme was present in the heart, aorta, kidney, pancreas, lung, liver, spleen, small intestine, and skeletal muscle. The amino acid composition of the enzyme was different from that of dog urinary kallikrein. Amino acid sequence analysis indicated that it is likely to be N-terminally blocked. The present study showed that this kallikrein-like enzyme is different from previously reported kallikrein and is distributed not only in the heart, but also in other tissues such as the aorta, kidney, lung, liver, spleen, small intestine, and skeletal muscle. This enzyme may exert local effects by generating kinins and Ang II.

Increased chymase-dependent angiotensin II formation in human atherosclerotic aorta

Locally formed angiotensin II (Ang II) and mast cells may participate in the development of atherosclerosis. Chymase, which originates from mast cells, is the major Ang II-forming enzyme in the human heart and aorta in vitro. The aim of the present study was to investigate aortic Ang II-forming activity (AIIFA) and the histochemical localization of each Ang II-forming enzyme in the atheromatous human aorta. Specimens of normal (n=9), atherosclerotic (n=8), and aneurysmal (n=6) human aortas were obtained at autopsy or cardiovascular surgery from 23 subjects (16 men, 7 women). The total, angiotensin-converting enzyme (ACE)-dependent, and chymase-dependent AIIFAs in aortic specimens were determined. The histologic and cellular localization of chymase and ACE were determined by immunocytochemistry. Total AIIFA was significantly higher in atherosclerotic and aneurysmal lesions than in normal aortas. Most of AIIFA in the human aorta in vitro was chymase-dependent in both normal (82%) and atherosclerotic aortas (90%). Immunocytochemical staining of the corresponding aortic sections with antichymase, antitryptase or anti-ACE antibodies showed that chymase-positive mast cells were located in the tunica adventitia of normal and atheromatous aortas, whereas ACE-positive cells were localized in endothelial cells of normal aorta and in macrophages of atheromatous neointima. The density of chymase- and tryptase-positive mast cells in the atherosclerotic lesions was slightly but not significantly higher than that in the normal aortas, and the number of activated mast cells in the aneurysmal lesions (18%) was significantly higher than in atherosclerotic (5%) and normal (1%) aortas. Our results suggest that local Ang II formation is increased in atherosclerotic lesions and that chymase is primarily responsible for this increase. The histologic localization and potential roles of chymase in the development of atherosclerotic lesions appear to be different from those of ACE.

Function and expression of a novel rat salt-tolerant protein: evidence of a role in cellular sodium metabolism

Higher dietary salt intake in humans is associated with higher BP, but the BP response to NaCl, so-called salt sensitivity, is heterogeneous among individuals. It has been postulated that modifications in cellular cation metabolism may be related to salt sensitivity in mammalian hypertension. The authors have isolated a novel rat complementary DNA, called salt-tolerant protein (STP), that can functionally complement Saccharomyces cervisiae HAL1, which improves salt tolerance by modulating the cation transport system. On high-salt (8% NaCl) diets, both Dahl salt-sensitive and salt-resistant rats displayed an elevated BP and increased STP mRNA expression. Immunohistochemistry using an anti-rat STP antibody demonstrated the presence of STP immunoreactivity in the proximal tubules. In cells that transiently expressed STP, the intracellular [Na+]/[K+] ratio was higher than that in control cells. STP contains predicted coiled-coil and Src homology 3 domains, and shows a partially high degree of nucleotide identity to human thyroid-hormone receptor interacting protein. These results suggest that STP may play an important role in salt sensitivity through cellular sodium metabolism by mediating signal transduction and a hormone-dependent transcription mechanism.

Differences in tissue angiotensin II-forming pathways by species and organs in vitro

Angiotensin (Ang) II plays an important role in cardiovascular homeostasis, not only in the systemic circulation but also at the tissue level, and is involved in the remodeling of the heart and vasculature under pathological conditions. Although alternative Ang II-forming pathways are known to exist in various tissues, the details of such pathways remain unclear. The aim of this study was to examine tissue Ang II-forming activities and to identify the responsible enzyme in several organs (lung, heart, and aorta) in various species (human, hamster, rat, rabbit, dog, pig, and marmoset). Among the organs examined, the lung contained the highest Ang II-forming activity. The responsible enzyme for pulmonary Ang II formation was angiotensin I-converting enzyme (ACE) in all of the species except the human lung, in which a chymaselike enzyme was dominant. In the heart, the highest total Ang II-forming activity was observed in humans, and a chymaselike enzyme was dominant in all of the species except rabbit and pig. Aorta exhibited a relatively high total Ang II-forming activity, with a predominance of chymaselike activity in all of the species except rabbit and pig, in which ACE was dominant. Our results indicate that there were remarkable differences in Ang II-forming pathways among the species and organs we examined. To study the pathophysiological roles of ACE-independent Ang II formation, one should choose species and/or organs that have Ang II-forming pathways similar to those in humans.

Genetic analysis of the epithelial sodium channel in Liddle's syndrome

BACKGROUND

Liddle's syndrome is an autosomal inheritable disorder that causes hypertension due to excess function of sodium channel.

OBJECTIVE

To analyze the DNA sequence of the amiloride-sensitive epithelial sodium channel (ENaC) in three patients who had low-renin hypertension with hypokalemia. The patients included a 24-year-old woman and her 20-year-old brother whose mother was hypertensive. The third patient was a 15-year-old girl with no family history of hypertension.

METHODS

The DNA sequence of the ENaC was analyzed as follows. Venous blood samples were collected from the patients and total genomic DNA was prepared by standard methods. Specific primers were used for direct polymerase chain reaction; one set of primers for amplifying the C terminus (codon 523-638) of the , subunit of ENaC, and two sets of primers for amplifying the C terminus (codons 525-587 and 568-650) of the y subunit of ENaC. Polymerase chain reaction products were purified and subjected to direct DNA sequence analysis.

RESULTS

Direct sequence analysis demonstrated the presence of a single-base substitution in one segment of the 0 subunit of ENaC, a C-T transition that changed the encoded Pro (CCC) at codon 616 to Ser (TCC) in the siblings (cases 1 and 2). In case 3, we found a missense mutation of Pro (CCC) to Leu (CTC) at codon 616. Case 3 is considered to be sporadic, since DNA sequencing of the PY motif of her parents gave normal results.

CONCLUSIONS

The DNA sequences of the ENaC in three patients with Liddle's syndrome were analyzed. In one family case, we found a new missense mutation of Pro (CCC) to Ser (TCC) at codon 616 in the 0 subunit of ENaC. A genetic analysis of the amiloride-sensitive epithelial sodium channel is recommended in assessing patients with low-renin, salt-sensitive hypertension whose blood pressure is not responsive to spironolactone treatment.

Plasma renin activity could be a useful predictor of left ventricular hypertrophy in essential hypertensives

To clarify the ability of clinical and laboratory parameters to reflect target organ damage, especially left ventricular hypertrophy (LVH), we investigated which of these parameters might correlate to LVH as determined by electrocardiographic voltage at the first clinic visit in 108 (53 males and 55 females, average age 52 +/- 10 years) untreated essential hypertensives. The sum of the amplitude of the S wave in lead V1 plus that of the R wave in lead V5 or V6 (SV1 + R(V5, V6)) was correlated with blood pressure in both males and females. In subjects with LVH (SV1 + R(V5, V6) > or = 3.5mV), a stepwise multiple regression analysis revealed that SV1 + R(V5, V6) was associated with plasma renin activity (PRA) in both males and females, and with creatinine concentration (Cr) in males. These results suggest that PRA at the first visit could be a useful predictor of LVH in patients with essential hypertension.

Mild exercise activates renal dopamine system in mild hypertensives

OBJECTIVE

The role of renal dopamine in the early depressor effect of exercise was evaluated in hypertensives.

METHODS

After a general clinical observation period of 4 weeks, 29 essential hypertensives were divided into two groups. The exercise group (n=16) underwent blood lactate threshold exercise using a cycle ergometer for 60 min three times a week for 4 weeks.

RESULTS

In the non-exercise group (n=13), blood pressure (BP) and humoral variables did not change significantly (from 150+/-3/93+/-2 to 145+/-2/94+/-1 mm Hg). In the exercise group (n=16), resting BP was significantly reduced from 158+/-2/92+/-2 at week 0 to 145+/-3/85+/-3 mm Hg at week 4. The increase in urinary free dopamine excretion (from 248+/-14 to 276+/-24 ng/mg Cr) at week 4 was significantly higher than that in the non-exercise group (from 220+/-31 to 196+/-27 ng/mg Cr). In the exercise group, urinary kallikrein activity also increased significantly from 173.0+/-35.4 at week 0 to 320.3+/-63.3 ng bradykinin/min/mg Cr at week 4. These changes in urinary free dopamine excretion and urinary kallikrein activity were negatively correlated with the change in BP. The change in urinary sodium excretion was also negatively correlated with the change in plasma volume index. Moreover, the change in urinary free dopamine excretion was positively correlated with the changes in urinary kallikrein activity and urinary sodium excretion. The change in renal decarboxylation rate of DOPA (3,4-dihydroxyphenylalanine) positively correlated with the changes in urinary free dopamine excretion and urinary sodium excretion, and was negatively correlated with the change in systolic BP.

CONCLUSION

These results suggest that exercise triggered renal dopamine generation and activation of renal kallikrein-kinin system, resulting in natriuresis and BP reduction in the early phase (4 weeks) of mild exercise.

Amlodipine lowers blood pressure without increasing sympathetic activity or activating the renin-angiotensin system in patients with essential hypertension

OBJECTIVE

Recent clinical studies suggest that the reflex increase in sympathetic nervous activity accompanying a reduction in blood pressure may contribute to the untoward effects of dihydropyridine calcium antagonists. The aim of this study was to examine whether plasma noradrenaline levels and renin activity are increased with the reduction of blood pressure during the initial phase of administration of the long-acting dihydropyridine calcium antagonist amlodipine.

METHODS

The effects of amlodipine on ambulatory blood pressure and on diurnal variations in plasma noradrenaline and renin activity were examined 1, 4, and 7 days after the start of amlodipine administration in eight inpatients with essential hypertension.

RESULTS

The 24-h mean systolic and diastolic blood pressure on day 7 was significantly lower than it was 1 day before the start of treatment. There was no change in the mean heart rate. The mean trough to peak ratios of systolic and diastolic blood pressure of seven patients were 61% and 71%, respectively. Diurnal patterns of plasma noradrenaline levels and renin activity 1, 4, and 7 days after the start of amlodipine administration were unchanged.

CONCLUSION

The antihypertensive effects of amlodipine were of slow onset and long duration and were not accompanied by an increase in sympathetic activity or activation of the renin-angiotensin system.

Purification and characterization of a kinin- and angiotensin II-forming enzyme in the dog heart

OBJECTIVE

To purify and characterize a kinin-forming enzyme in the dog heart and to examine the ability of this enzyme to generate angiotensin (Ang) II from Ang I.

METHODS

The enzyme was isolated from heart homogenate using a diethylaminoethyl-Sepharose column, an aprotinin affinity column and a wheat germ lectin-Sepharose 6MB column. Kininogenase activity was assessed with a kinin radioimmunoassay after samples had been incubated with bovine low-molecular-mass kininogen at 37 degrees C for 1 h. Ang I-converting activity was assessed by the quantitation of Ang II formed by incubation of the sample with Ang I at 37 degrees C for 3 h, using high performance liquid chromatography. The enzyme was subjected to 12.5% sodium dodecyl sulphate-polyacrylamide gel electrophoresis, stained by Coomassie brilliant blue and transferred electrically to a membrane with glycoprotein staining.

RESULTS

The purified enzyme is a glycoprotein with an apparent relative molecular mass of 65 kDa by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. Its kininogenase activity was approximately 20 micrograms bradykinin/h per mg protein at an optimal pH of 8.0. The enzyme also converted Ang I to Ang II at an optimal pH of 6.5. Its specific activity was approximately 2 micrograms Ang II/h per mg protein. Both activities were inhibited by aprotinin, a tissue kallikrein inhibitor. Western blot analysis using polyclonal antibody against this enzyme demonstrated that this enzyme exists both in the myocardium and in the coronary artery.

CONCLUSIONS

The present study showed that the kinin-forming enzyme in the dog heart is a kallikrein-like enzyme that is different from cathepsin D, cathepsin G and chymase. It is also able to Ang I to Ang II. This enzyme might play a role in regulating myocardial perfusion, mainly by generating kinins and in part by forming Ang II.

Molecular cloning of a novel rat salt-tolerant protein by functional complementation in yeast

To elucidate the genetic basis of salt-sensitivity in mammalian hypertension, we isolated six rat complementary DNAs by functional complementation in yeast. These genes were able to substitute for the salt-tolerant activity of HALI which confers salt tolerance by modulating the cation transport system in yeast. We identified these genes as beta-globin, lambda-crystallin, androgen-regulated protein, mitochondrial cytochrome b, a homologue of infant brain cDNA, and a novel gene, called salt-tolerant protein (STP). STP contains 1964 bp nucleotides and an open reading frame which encodes 496 amino acid residues. Northern blot analysis showed that STP mRNA is expressed in various rat tissues.

Role of endogenous ouabain-like substance during graded exercise in hypertensive individuals

Changes in plasma endogenous ouabain-like substance (EOLS) and plasma noradrenaline, along with changes in blood pressure (BP), heart rate, and blood lactate concentration, were investigated in hypertensive individuals during strenuous exercise testing. Thirteen (4 men and 9 women) middle-aged (34-63 years, mean 50 +/- 2 years) patients with mild essential hypertension underwent graded multistage submaximal exercise testing on a cycle ergometer. The workload in each exercise test was increased depending on the individual's physical fitness until they reached 75-80% of the predicted age-adjusted maximal heart rate prescribed by the American College of Sports Medicine. Systolic (S) BP rose by 67 +/- 9 mm Hg (P < 0.001), mean (M) BP by 28 +/- 3 mm Hg (P < 0.001), diastolic (D) BP by 9 +/- 2 mm Hg (P < 0.005) and heart rate by 79 +/- 6 beats/min (P < 0.001) after submaximal graded exercise. The blood lactate concentration and plasma noradrenaline increased significantly (+3.40 +/- 0.34 mmol/l and +895 +/- 94 pg/ml respectively, P < 0.001). Although the change in EOLS was not significant, it showed a strong positive correlation with the change in plasma noradrenaline (R = 0.760, P < 0.001). These results suggest that EOLS may participate in modifying sympathetic vasoconstriction during submaximal graded exercise.

Plasma free and sulfoconjugated dopamine before and after a half-marathon

To elucidate whether increased plasma levels of free dopamine (F-DA) after exercise are due to deconjugation of sulfoconjugated (S-) DA in plasma, we compared the changes in plasma F- and S- DA, as well as changes in both the S- and F- forms of epinephrine (E) and norepinephrine (NE), after running a half-marathon. Free catecholamines (F-CAs) were measured by automated high-performance liquid chromatography (HPLC). Total (F+S) CAs were determined using an efficient deconjugation method as follows; 1200 microliters plasma was incubated with 152 mU arylsulfatase (AS) for 30 min at pH 7.6. The plasma levels of F-CA (pg/ml) (mean +/- SEM) all increased significantly (p < 0.01) after the half-marathon; i.e., F-DA increased from 13.3 +/- 5.7 to 176.3 +/- 32.2; F-E from 58.0 +/- 12.3 to 764.3 +/- 136.4; F-NE from 246.6 +/- 15.2 to 3082.0 +/- 690.3. OF S-CAs, S-E (from 127.8 +/- 26.0 to 1218.2 +/- 190.8) and S-NE (from 717.1 +/- 61.6 to 5586.9 +/- 761.9) also increased, but, in contrast, among the S-CAs, only the increase in S-DA (from 5324.9 +/- 1967.3 to 7359.6 +/- 1627.9) was not statistically significant. Sulfoconjugation may play an important role in inactivating F-DA as well as F-NE and -E, that are released into plasma in response to vigorous exercise. Thus, plasma F-DA is unlikely to be derived through deconjugation of plasma S-DA.

Human urinary kallikrein can generate angiotensin II from homologous renin substrates

We previously proposed the "kinin-tensin system," a unique vasoregulatory system that can produce both angiotensin II and kinins. To verify whether tissue kallikrein is a part of this system in humans, we examined the ability of human urinary kallikrein (HUK) to generate angiotensin (ANG) II directly from homologous renin substrates such as purified human angiotensinogen (AOGEN) and authentic human tridecapeptide renin substrate (13 RS). HUK released ANG II not only from ANG I but also directly from both AOGEN and 13RS at an optimum pH of 7.0. The amount of generated ANG II from 7.5 nmol of each of the three substrates at pH 7.0 was as follows: ANG I, 292.7 +/- 67.2; 13 RS, 1951.7 +/- 239.6; AOGEN, 2.2 +/- 0.3 (pmol/3h, n = 3 mean +/- SE). HUK cleaved Phe-His and His-Leu bonds in 13 RS, and Tyr-Ile and Phe-His bonds in ANG I. These results suggest that HUK is a part of the "kinintensin system", i.e., HUK can not only release kinins, but can also generate ANG II mainly through ANG I conversion and from AOGEN, the latter being a minor source of ANG II. Furthermore, HUK may play a role in regulating vascular tone under certain conditions in vivo.

Angiotensin II formation by an alternative pathway during exercise in humans

OBJECTIVE

We postulated a 'kinin-tensin system' in which angiotensin II (Ang II) is cleaved by one or more serine protease independent of renin or angiotensin converting enzyme (ACE). The aim was to determine whether this alternative Ang II-forming pathway by serine proteases participates in the rise in plasma levels of Ang II during exercise in humans.

DESIGN AND METHODS

The study consisted of two double-blind crossover experiments. in experiment 1 six healthy volunteers who had been taking either placebo (group P) or the ACE inhibitor captopril (150 mg/day for 3 days; group C) performed a cycle ergometer graded exercise test at four different exercise intensities: stage 1, half of the intensity at the blood lactate threshold (WLT); stage 2, the intensity at WLT; stage 3, the intensity at 4 mmol/l blood lactate; and stage 4, an intensity between stage 3 and maximum intensity. In experiment 2 the same volunteers took captopril (150 mg/day for 3 days) and performed exercise at an intensity corresponding to 90% of the 4 mmol/l blood lactate intensity for 30 min during intravenous drip injection of a serine protease inhibitor, nafamostat [NAF; 0.2 mg/kg per h; NAF(+) group] or saline [NAF(-) group].

RESULTS

In experiment 1 plasma Ang II levels increased from at rest to after exercise in both groups P and C. Although there was a significant treatment effect, captopril did not significantly alter the exercise-induced changes in Ang II level. In experiment 2 the increase in Ang II level after 30 min exercise in the NAF(+) group was significantly lower than in the NAF(-) group.

CONCLUSIONS

These results suggest the presence of an alternative Ang II-forming pathway independent of ACE, and that one or more NAF-sensitive serine protease is responsible, at least partly, for generating Ang II during exercise.

Urinary kallikrein activity is increased during the first few weeks of exercise training in essential hypertension

OBJECTIVE

To determine whether the renal kallikrein-kinin and dopamine systems participate in lowering blood pressure during mild exercise in hypertensives.

DESIGN

After a general clinical observation period of 4 weeks, 27 essential hypertensives were divided into two groups. The exercise group underwent blood lactate threshold exercise, using a cycle ergometer for 60 min three times a week for 10 weeks. The non-exercise group was observed at the outpatient clinic. Blood pressure and humoral parameters were measured at weeks 0, 1, 2, 4 and 10 in both groups.

METHODS

Blood pressure was measured indirectly with an automatic blood pressure recorder. Twenty-four-hour urinary kallikrein activity (by kininogenase assay), total or free dopamine and total noradrenaline (by high-performance liquid chromatography) were also measured.

RESULTS

In the non-exercise group blood pressure and humoral parameters did not change. In the exercise group the change in resting blood pressure between weeks 0 and 10 was statistically significant. The change in 24-h urinary kallikrein activity of the exercise group was significantly greater than that of the non-exercise group between weeks 0 and 1 and weeks 0 and 2. Moreover, the change in systolic blood pressure (SBP) between weeks 0 and 2 was negatively correlated with the change in urinary kallikrein activity between weeks 0 and 2, the change in total dopamine between weeks 0 and 2 was negatively correlated with the change in diastolic blood pressure in the same period, and the change in SBP between weeks 0 and 10 was positively correlated with the change in total noradrenaline in the same period in the exercise group. Subjects with a relatively high baseline urinary kallikrein activity had a significantly greater change in SBP between weeks 0 and 10 than subjects with a relatively low baseline activity.

CONCLUSIONS

The renal kallikrein-kinin and dopamine systems may participate in lowering blood pressure during the first few weeks of exercise training. The subsequent reduction of sympathetic activity may be involved in maintaining the lowered blood pressure. Mild exercise is more effective in reducing blood pressure in hypertensives who have a relatively high basal renal kallikrein-kinin system activity.

Taurine amplifies renal kallikrein and prevents salt-induced hypertension in Dahl rats

OBJECTIVE

To determine whether taurine reduces blood pressure by stimulating the renal kallikrein-kinin system.

METHODS

The effects of taurine on blood pressure, urinary kallikrein activity and renal kallikrein gene expression were investigated in Dahl salt-sensitive (Dahl-S) rats. The specificity of the action of taurine was verified by comparison with the action of beta-alanine, a carboxylic analogue of taurine. The effect of co-administration of the specific bradykinin B2 receptor antagonist Hoe 140 was also examined.

RESULTS

Administration of taurine (3% in drinking water) for 4 weeks retarded the development of salt (4% sodium chloride diet)-induced hypertension. Systolic blood pressure at the end of the experiment was significantly higher in control rats than in taurine-treated rats. Urinary sodium excretion was not decreased by the reduction in blood pressure. The heart weight:body weight ratio was significantly lower, and urinary volume and kallikrein excretion were significantly higher, in taurine-treated rats. Renal kallikrein gene expression at weeks 1 and 4 was higher in taurine-treated rats. Systolic blood pressure 3 and 4 weeks after the administration of beta-alanine was slightly, but not significantly, lower than that of untreated rats on a high-salt diet, and was accompanied by a significantly lower body weight. Urinary kallikrein excretion decreased with a high-salt diet regardless of beta-alanine administration. Continuous systemic administration of Hoe 140 did not cause any significant alteration in blood pressure in Dahl-S rats that received taurine with a high-salt diet. Taurine also showed a renoprotective effect, as judged by a reduction in proteinuria.

CONCLUSION

These results suggest that taurine is an effective antihypertensive agent for salt-induced hypertension. Although taurine activated renal kallikrein, further studies are required to confirm the participation of activated kallikrein in the antihypertensive, cardioprotective and renoprotective effects of taurine.

Central squamous cell carcinoma of the mandible. Computed tomographic findings

Five cases of central squamous cell carcinoma of the mandible were investigated with the use of computed tomography. Bucco-lingual extent and spread along the mandibular division of the trigeminal nerve were evaluated. Three patients with trismus showed involvement of the masseter or medial pterygoid muscle on computed tomography. Involvement of more than two landmarks along the trigeminal nerve were observed in cases with both paresthesia of the lower lip and severe pain that resembled neuralgia. Perineural invasion was confirmed histologically in four cases, and all of these patients had both severe pain and mandibular canal involvement that could be demonstrated with computed tomography. When localized soft tissue changes are evident along the course of the trigeminal nerve in the region between the mandibular foramen and foramen ovale, ascending perineural spread should be suspected. Computed tomography findings correlated well with clinical symptoms but added information about the spread of the lesion within the surrounding soft tissue.

Mandibular reconstruction using hydroxylapatite granules, autogenous bone, and a cervical island skin flap

Ten patients with gingival carcinoma who were treated by marginal mandibulectomy were reconstructed using hydroxylapatite granules, autogenous bone chips, and a cervical island skin flap. The cervical flap was used to produce a cover and partition, designed to prevent the displacement of the mixture of hydroxylapatite and bone. Reconstruction was successfully achieved in all patients. Loss of height of the reconstructed mandible over an average 18-month follow-up ranged from 8% to 22%. One patient has worn a full denture and five patients wear partial dentures.

Crossover comparison between the depressor effects of low and high work-rate exercise in mild hypertension

1. The relationship between work-rate and the antihypertensive effect of exercise in hypertensives, and the mechanism of that effect, were investigated by a crossover clinical trial. 2. Ten mild hypertensives were randomly divided into two groups. One group performed low work-rate exercise (LWE) on a cycle ergometer for 10 weeks (blood lactate threshold; approximately 50% of maximum oxygen consumption [Vo2max]). After a 10 week interval without exercise training, these subjects were then switched to a high work-rate exercise (HWE) regimen (4 mmol/L of blood lactate; approximately 75% of Vo2max) for another 10 weeks. In the other group, the order of exercise training was reversed. Since two patients withdrew from the protocol during HWE periods, statistical analysis was performed on the data from the remaining eight patients. There were no order effects observed in any of the data from the two groups. 3. During both LWE and HWE, resting blood pressure (BP) fell significantly after the initiation of exercise therapy (P < 0.05). Furthermore, the overall effects of 10 weeks of LWE and HWE on BP were not significantly different. 4. The work-rate at the lactate threshold, which reflects physical fitness, had increased significantly by 16 W (P < 0.01) after the LWE period and by 11 W (P < 0.01) after the HWE. 5. During the LWE period, changes in haemodynamic and humoral variables were not significant, except for a reduction in plasma norepinephrine at week 10 (P < 0.05). In the HWE period, changes in haemodynamic and humoral variables were not significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Beneficial effects of a serine protease inhibitor in peripheral vascular disease

Kallikrein, a serine protease known to generate bradykinin (a vasodilating peptide) in alkaline conditions, also generates angiotensin II (a vasoconstricting peptide) in weak acidic conditions. Based on this previous observation, the present study was performed to determine whether ischemic muscle tissue, in which the regional pH must decrease, produces angiotensin II by kallikrein or a similar enzyme, and whether nafamostat (NAF), a serine protease inhibitor, improves local hemodynamics under ischemic conditions caused by exercise in patients with ischemic peripheral vascular disease. NAF was administered intravenously to 20 patients with peripheral vascular disease. Lower-limb thermograms and blood flow were measured before and after exercise. Femoral venous blood of affected limbs was obtained to measure viscosity and humoral variables (i.e., pH, lactate, angiotensin II and bradykinin). Walking distance and subjective symptoms were also recorded. As a control, the same patients repeated this test with saline infusion on a separate day. NAF significantly increased maximal walking distance, improved subjective symptoms during exercise, and attenuated exercise-induced venous lactate and blood viscosity increases, and pH reduction. The blood viscosity increase correlated with the lactate increase. Pretreatment with NAF also resulted in a higher lower-limb skin temperature, and a greater increase of blood flow in the lower limbs after exercise than did pretreatment with saline. The results suggest that kallikrein-like serine protease may exacerbate ischemic symptoms. Changes in plasma bradykinin and angiotensin II in the femoral vein were not detectable, probably because of the lower levels of these peptides in the peripheral circulation.

[A case of idiopathic hyperaldosteronism diagnosed by adrenal imaging]

We report a case of idiopathic hyperaldosteronism (IHA) which was differentiated from an aldosterone producing adenoma by the adrenal imaging techniques with computed tomography (CT) and scintigraphy. In this patient, the high basal aldosterone level with the suppressed plasma renin activity typically indicated the diagnosis of primary aldosteronism. However, the differentiation from an aldosterone producing adenoma by responses of plasma aldosterone levels to upright posture, captopril or adrenocorticotropic hormone (ACTH) administration was not definitive. Abdominal CT revealed bilateral adrenal swelling. Adrenal scintillation scanning with 131I-iodocholesterol showed bilateral uptake even after the administration of dexamethasone. Blood sampling from the right adrenal vein was unsuccessful. Blood pressure and serum potassium levels remained unchanged during dexamethasone administration (2 mg/day) over ten days. After the administration of spironolactone and nisoldipine blood pressure and serum potassium levels were normalized. Adrenal imaging is considered to be very useful for the diagnosis of IHA.

Role of locally formed angiotensin II and bradykinin in the reduction of myocardial infarct size in dogs

OBJECTIVE

The aim was to investigate the role of local formation of angiotensin II and bradykinin in the reduction of myocardial infarct size.

METHODS

Bilaterally nephrectomised male mongrel dogs were used. Effects were compared of pretreatment with three inhibitors of angiotensin II forming enzyme-captopril (an angiotensin converting enzyme inhibitor), nafamostat (a serine protease inhibitor), and chymostatin (a cysteine protease inhibitor)--on left anterior descending coronary artery occlusion. Haemodynamic variables were monitored and blood was collected from the anterior interventricular vein and the aorta. Angiotensin I, angiotensin II, and bradykinin were measured by radioimmunoassay. After 90 min of occlusion, infarct sizes were determined by a macroscopic enzyme technique.

RESULTS

Angiotensin II release into the anterior interventricular vein increased from 0.03(SEM 1.19) pg.min-1 (before coronary occlusion) to 4.64(1.37) pg.min-1 (n = 14, p < 0.05), while angiotensin I release and plasma renin activity remained unchanged. The increase in angiotensin II release was inhibited by nafamostat and chymostatin, but not by captopril. Bradykinin release increased from -3.18(2.72) (before coronary occlusion) to 34.7(12.3) pg.min-1 (n = 14 p < 0.05) by 30 min after occlusion. This increase was augmented by captopril, from 4.10(2.86) before occlusion to 97.8(39.6) pg.min-1 at 5 min after occlusion (n = 12, p < 0.05), but not by nafamostat or chymostatin. Infarct size was smaller (p < 0.05) in the captopril group than in the control group.

CONCLUSIONS

Angiotensin II is locally produced in the ischaemic heart by both serine protease(s) and chymostatin inhibitable protease(s), but not by angiotensin converting enzyme. From the reduction in myocardial infarct size produced by angiotensin converting enzyme inhibition, it seems that bradykinin accumulation may play a more important role than the suppression of angiotensin II formation.

Clinical symptoms of open lock position of the condyle. Relation to anterior dislocation of the temporomandibular joint

Nine cases of open lock position of the condyle of the temporomandibular joint (TMJ) are reported. In two patients recurrent dislocation of the TMJ was diagnosed clinically, and four had previous episodes of anterior dislocation. An arthrotomographic examination revealed that the condyles of the affected TMJs were located anterior to the anterior bands of the disks at an open-mouth position. An arthrographic fluoroscopic examination showed that the anterior bands mechanically obstructed the anteriorly displaced condyles from posterior movement into the articular fossae to various degrees at open-mouth position. One cause of anterior dislocation of the TMJ is thought to be fixation of the condyle in the open lock position resulting from a disturbance of a neuromuscular mechanism. In the two patients with dislocation, occlusal treatment eliminated muscular symptoms and the dislocations completely disappeared.

Active and inactive renin after exercise

The effects of graded exercise on plasma concentrations of active and inactive renin were studied in seven healthy men. Exercise was performed on a cycle ergometer at four different exercise intensities (corresponding to 30%, 50%, 80% and 87% of VO2max) for 10 min each. Concentrations of active renin and total renin after activation by trypsin were measured by direct immunoradiometric assay. Non-trypsin-activated renin concentration (inactive) was obtained by subtraction. Active renin concentrations at 30%, 50%, 80% and 87% of VO2max were 1.2, 1.9, 3.1 and 4.6 times higher than the control concentration, respectively. Similar increases in plasma renin concentration, determined by conventional enzymatic assay, were observed at every stage. In contrast, changes in inactive renin concentration were not significant at any stage. Significant increases in noradrenaline concentration were found at every exercise stage, but adrenaline, aldosterone and lactate concentrations were significantly elevated only after exercise at 50%, 80% and 87% of VO2max. The similarity between the changes in concentration of active renin and noradrenaline would suggest that sympathetic nerve activity may have been responsible either for the release of active renin or for the conversion of inactive renin to its active form in the kidney.

Human renin activation by protease from the renin granule fraction of the dog kidney cortex

To clarify the possible conversion of prorenin in renin granules where conversion reportedly occurred, we investigated whether the renin granule fraction of the kidney could activate prorenin to the active form. Renin granules were isolated from the dog kidney cortex by discontinuous sucrose density gradient centrifugation. Human active renin was quantified by immunoradiometric assay which could detect only the human active renin but not the inactive human renin or dog renin. Inactive renin from human amniotic fluid was incubated with the subcellular fraction of the dog kidney cortex. The renin granule fraction that showed the highest renin activity stimulated the inactive renin to become the active form. The membrane preparation obtained from the renin granule fraction by freezing and thawing the fraction in low osmolarity retained the activity of renin activation. Other subcellular fractions showed less renin activation. The optimal pH for renin activation by the membrane was pH 5.0 to 6.0. The activation depended on the time of incubation and concentration. The activation was inhibited by N-ethylmaleimide but not by EDTA or serine protease inhibitors. These results suggest that renin is processed by a membrane bound protease in renin granules.

[A rare adult case of double-outlet right ventricle without pulmonary stenosis: an autopsy case]

Double outlet right ventricle (DORV) is a rare cardiac malformation especially in adulthood. We report a woman with DORV who survived to the age of 33 years. She had not been seriously limited, before she visited our hospital for cardiac evaluation at the age of 25 years. She was cyanotic, and had clubbing of fingers and toes and facial edema. Holosystolic murmur and diastolic regurgitant murmur were audible along the left sternal border. Chest X-ray showed cardiomegaly and enlarged pulmonary trunks. Electrocardiography showed right axis deviation and biventricular hypertrophy. Laboratory examination revealed polycythemia (Hb: 22.4 g/dl), increased levels of hepatic enzymes due to congestive liver and marked hypoxemia (Pao2: 40 mmHg), Diagnosis of DORV was made with cardioangiography. Surgical repair was not indicated. Thereafter, she experienced recurrent heart failure which progressed gradually. She died probably of ventricular arrhythmia at the age of 33 years. At autopsy, the heart showed dilatation of the right atrium and ventricle, and hypertrophy of the bilateral ventricles. Both the pulmonary artery without stenosis and the aorta originated completely from the right ventricle, which were almost normally positioned with bilateral conus. Large ventricule septal defect was found at the subaortic portion. Patent ductus arteriosus and preductal aortic coarctation co-existed. To our knowledge, few cases with DORV who survived over 30 years have been reported, and they all manifested pulmonary stenosis. The present case is a very rare DORV that survived over 30 years without the complication of pulmonary stenosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Inhibitory effects of kinins on angiotensin I conversion in the local circulation

The inhibition of angiotensin converting enzyme (ACE) by kinins was studied using bradykinin (BK), lysyl-bradykinin (Lys-BK), [Hydroxyproline3]-bradykinin ([Hyp3]-BK) and [Hydroxyproline3]-lysyl-bradykinin ([Hyp3]-Lys-BK). The latter two are novel kinins recently identified in our laboratory. All the four kinins displayed competitive inhibition on the conversion of angiotensin I to angiotensin II by purified canine lung ACE. Inhibition constants (Ki) for the four kinins were estimated from Dixon's plot as follows-BK: 0.27 microM, Lys-BK: 0.57 microM, [Hyp3]-BK: 0.34 microM, and [Hyp3]-Lys-BK: 0.27 microM. In the rat hindlimb perfusion system, the kinins were demonstrated to partially inhibit angiotensin I conversion to angiotensin II by the vascular ACE. Taken together, these results suggest that angiotensin II formation by ACE in the vascular tissue is possibly inhibited by local kinins, especially after ACE inhibitor administration. This indirect action of kinins, coupled with its direct vasodilatory action, might indicate a cooperative participation in vasodilation.

Substrate-dependent angiotensin II formation in the peripheral circulation

An alternative angiotensin II-forming system distinct from the vascular renin-angiotensin system was demonstrated using a rat hindlimb perfusion system and synthetic substrates. This pathway was resistant to captopril and aprotinin, but was highly sensitive to chymostatin. Moreover, angiotensin II formation was substrate-dependent, i.e. angiotensin II formation from tridecapeptide human renin substrate in the presence of captopril was more than twice than that from an equimolar amount of angiotensin I. Both pathways may play a role in regulating the peripheral circulation.

A case of a clinically "silent" pheochromocytoma

A case of a clinically "silent" pheochromocytoma is presented. The adrenal mass was incidentally discovered by abdominal ultrasonography and computed tomography. In the course of hospitalization, the patient was normotensive and asymptomatic. Plasma catecholamine levels were nearly normal, whereas urinary levels of catecholamine metabolites were slightly elevated. A glucagon provocative test and 131I-metaiodobenzylguanidine scintigram were useful for diagnosing such an atypical pheochromocytoma. A discussion of clinically-unsuspected pheochromocytoma is also presented.

Angiotensin-converting activity of tissue kallikrein

This study examined the ability of tissue kallikreins, purified from both rat submandibular gland (SMG) and human urine, to form angiotensin II from synthetic angiotensin I. Both kallikreins converted angiotensin I to angiotensin II at neutral pH with the following kinetic constants: SMG kallikrein, Km = 9.43 x 10(-5) mol/l, Kcat = 1.58 mumols/mg protein/min; human urinary kallikrein, Km = 1.71 x 10(-4) mol/l, Kcat = 0.06 mumol/mg protein/min. These activities were not affected by angiotensin-converting enzyme (ACE) inhibitor. These results suggest that tissue kallikrein might participate in the formation of angiotensin II during administration of an ACE inhibitor.

High-renin malignant hypertension secondary to an aldosterone-producing adenoma

Malignant hypertension and high plasma renin activity was found in a 39-year-old woman with an aldosterone-producing adenoma. Only 3 similar cases have been previously reported, and all patients died before or after identification of the adenoma. The present paper documents the first reported case of a successfully managed high-renin malignant hypertension secondary to an aldosterone-producing adenoma. Regardless of its sporadic occurrence and common presence with low plasma renin activity, primary aldosteronism should be considered as a possible underlying cause of high-renin malignant hypertension.

Effects of the angiotensin converting enzyme inhibitors captopril, rentiapril, and alacepril in patients with essential and renovascular hypertension

The effects of captopril, rentiapril, and alacepril were compared in five patients with renovascular hypertension (RVH) and five with essential hypertension (EH). The dose of each drug was equivalent to 50 mg of captopril. Rentiapril inhibited angiotensin converting enzyme activity more strongly and for longer periods than did the other two drugs. In the patients with RVH, blood pressure was significantly reduced more quickly and for longer periods by rentiapril than by captopril or alacepril; in the patients with EH, alacepril was the most potent antihypertensive agent. The results indicate that rentiapril is as effective as the other two drugs in patients with hypertension and that alacepril is more effective in patients with low-renin hypertension or renin-independent hypertension than captopril or rentiapril.

Abdominal aortic aneurysm of unknown origin and renovascular hypertension in a 25 year old male

A 25 year old male had an abdominal aortic aneurysm involving bilateral renal arteries. Aortography revealed no irregularity in the aortic wall but a slight kinking at the tenth thoracic level followed by a fusiform aneurysm. Computed tomography (CT) showed an enlarged aortic lumen with an intraluminal thrombus. Plasma renin activity (PRA) was markedly increased (11 ng/ml/h), and the administration of captopril caused a further increase in PRA with a significant reduction in blood pressure, indicating the presence of renovascular hypertension. Abdominal aneurysm in a young adult is very rare. The etiology of the aneurysm appears to be idiopathic.

[Prolapse of the buccal fat pad in infant]

Two infant cases with traumatic prolapse of the buccal fat pad were presented. They suffered injuries from objects held in the mouth, such as a spoon and a tooth brush. Both received surgical treatment under local anesthesia, including closure of the wound with sutures. As the prolapsed tissue was fresh in the first case, it was repositioned. However, since the second case had passed 3 days after the accident and had a sign of infection, the prolapsed tissue was totally removed. Postoperative course was uneventful and there was no recurrence in both cases.

Isolation of [hydroxyproline3]Lysyl-bradykinin formed by kallikrein from human plasma protein

[Hydroxyproline3]Lysyl-bradykinin ([Hyp3]Lys-BK), a new kinin was isolated, besides Lysyl-bradykinin (Lys-BK), from the reaction mixture of human plasma protein Cohn's fraction IV-4 with hog pancreatic kallikrein. The liberated kinins were isolated by procedures including ethanol extraction, Sephadex G-15, CM cellulose and reverse-phase high performance liquid chromatography and quantitated by radioimmunoassay. On HPLC, two peaks of immunoreactive kinins emerged. Peak 1, an unknown kinin proceeded to peak 2 which had an identical retention time to that of Lys-BK. The amino acid sequence of the unknown peak 1 proved to be Lys-Arg-Pro-Hyp-Gly-Phe-Ser-Pro-Phe-Arg, or [Hydroxyproline3]Lys-BK, and peak 2 Lys-BK. The ratio of the amounts of two kinins thus formed were [Hyp3]Lys-BK 25 +/- 4% and Lys-BK 75 +/- 4%. The existence of [Hyp3]Lys-BK suggests a presence of a new kininogen containing [Hyp3]Lys-BK in human plasma protein.

Identification of [hydroxyproline3]-bradykinin released from human plasma and plasma protein Cohn's fraction IV-4 by trypsin

Aside from bradykinin (BK), a novel kinin, [Hydroxyproline3]-bradykinin ( [Hyp3]-BK), was isolated from the reaction mixture of human plasma and plasma protein Cohn's fraction IV-4 with trypsin. The liberated kinins were isolated based on procedures which we previously described for the isolation of [Hyp3]-lysyl-bradykinin ( [Hyp3]-Lys-BK) formed by kallikrein. The ratio of the amounts of two kinins thus formed from human plasma protein Cohn's fraction IV-4 were [Hyp3]-BK 25 +/- 4% and BK 75 +/- 4%, similarly to that of [Hyp3]-Lys-BK and Lys-BK, formed by kallikrein, but it varied by persons. The isolation of [Hyp3]-BK and [Hyp3]-Lys-BK suggests that a novel kininogen containing hydroxyproline in the third position of the bradykinin sequence in human plasma protein, possibly undergone post-translational modifications.

[Pulmonary tuberculosis in patients with oral cancer]

During an 11 year period, from 1976 to 1986, 33 (10.1%) out of 328 patients with oral cancer treated at our clinic had either a scarred pulmonary tuberculosis (TB) or active TB. Four of these 33 patients developed active TB. In two of these cases TB occurred before the therapy of oral cancer commenced and in the other two, after the operation for oral cancer. In one of the 4 cases, a recrudescence of the TB was suspected. Five cases that were suspected of having TB on analysis of their chest X-rays were administered prophylactic anti-tuberculous chemotherapy, after which no recrudescence or onset of TB.

Identification of [hydroxyproline3]-lysyl-bradykinin released from human plasma protein by kallikrein

[Hydroxyproline3]-lysyl-bradykinin [( Hyp3]-Lys-BK), a new kinin was isolated, besides lysyl-bradykinin (Lys-BK), from the reaction mixture of human plasma protein Cohn's fraction IV-4 with hog pancreatic kallikrein. The liberated kinins were isolated by procedures including ethanol extraction, Sephadex G-15, CM cellulose and reverse-phase high performance liquid chromatography (HPLC) and quantitated by radioimmunoassay. On HPLC, two peaks of immunoreactive kinins emerged. Peak 1, an unknown kinin proceeded to Peak 2 which had an identical retention time to that of Lys-BK. The amino acid sequence of the unknown Peak 1 proved to be Lys-Arg-Pro-Hyp-Gly-Phe-Ser-Pro-Phe-Arg, or [Hyp3]-Lys-BK, and Peak 2 Lys-BK. The ratio of the amounts of two kinins thus formed were [Hyp3]-Lys-BK 25 +/- 4% and Lys-BK 75 +/- 4%. The existence of [Hyp3]-Lys-BK suggests a presence of a new kininogen, containing [Hyp3]-Lys-BK in human plasma protein, possibly undergone post-translational modifications.

Formation of angiotensin II by tonin-inhibitor complex

Enzymatic activity of tonin-alpha 1-macroglobulin complex was studied in vitro and in vivo, using an immunoimmobilization technique. Tonin-alpha 1-macroglobulin complex, which was immunologically immobilized by anti-alpha 1-macroglobulin antibody covalently coupled to agarose gels, could quantitatively hydrolyze angiotensin I and synthetic tridecapeptide renin substrate to form angiotensin II. However, the solid-phase antibody-bound tonin-alpha 1-macroglobulin complex could not hydrolyze the plasma protein renin substrate. Phenylmethylsulfonyl fluoride, a serine protease inhibitor, inhibited both free tonin and the solid-phase antibody-bound tonin-alpha 1-macroglobulin complex. The hydrolytic activity of the solid-phase antibody-bound tonin-alpha 1-macroglobulin complex against angiotensin I was not inhibited by soybean trypsin inhibitor (molecular weight, 23,000), a potent inhibitor of free tonin. Taken together, these results suggest that tonin bound to alpha 1-macroglobulin keeps the active site intact and that inhibition of the enzyme activity is due to a steric hindrance. When 500 microliter of tonin was administered intravenously to rats, the immunoimmobilization method was used to show that the tonin-alpha 1-macroglobulin complex in the plasma formed angiotensin II. Thus, the tonin-alpha 1-macroglobulin complex in the plasma may be linked to some forms of hypertension through angiotensin II formation.