Biomedical subjects

M Sasaguri

Publications and source records attributed to M Sasaguri.

51 records · Page 3Linked to original sources

PubMed1990

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.

Angiotensin I↗

PubMed1990

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.

Adenoma↗

PubMed1990

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.

Angiotensin I↗

PubMed1990

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.

Angiotensin I↗

PubMed1990

[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)

Adult↗

PubMed1989

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.

Amino Acid Sequence↗

PubMed1989

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.

Adult↗

PubMed1989

[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.

Adipose Tissue↗

PubMed1988

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.

Amino Acids↗

PubMed1988

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.

Amino Acid Sequence↗

PubMed1988

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.

Angiotensin I↗

PubMed1988

[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.

Adult↗

PubMed1987

Small, bilateral, calcified intrarenal aneurysms--a case report.

With increased use of renal angiography and ultrasonography, intrarenal aneurysms and arteriovenous malformations have been easily diagnosed. The authors report a case of small, bilateral intrarenal aneurysms with calcifications that were associated with a visible pulsatile wall motion recorded by M-mode ultrasonography. The finding of selective renal angiography was consistent with bilateral intrarenal aneurysms. Accelerated atherosclerosis and long-term history of hypertension were thought to have caused them.

Aged↗

PubMedDate not supplied

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.

3-Iodobenzylguanidine↗

PubMedDate not supplied

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.

3-Mercaptopropionic Acid↗