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Biomedical subjects

T Ogihara

Publications and source records attributed to T Ogihara.

At least 793 records · Page 44Linked to original sources
PubMed1987

The effect of low dose carvedilol on circadian variation of blood pressure in patients with essential hypertension.

The effect of once daily low-dose carvedilol on circadian variations of blood pressure (BP) was studied in Japanese patients with mild or moderate essential hypertension. Thirty-one patients were admitted to hospital whose BP was 150/90 mm Hg/day or greater and they participated in the study. After a placebo period of 1 week, 5 or 10 mg carvedilol was given once daily in the morning for 3 to 7 days, and if BP reduction was not sufficient, the dose was increased to 20 mg daily. The blood pressure variation was monitored before and 1, 2, 4, 6, 8, 10, 12, and 24 h after administration of the drug on the last day of placebo and final dose of carvedilol. Of the 31 cases receiving carvedilol once daily, cumulative effectiveness (13 mm Hg reduction in mean BP) was 48.4% at 10 mg/day and 54.8% at 20 mg/day. Both systolic and diastolic pressures decreased significantly and heart rate decreased slightly. There was no significant difference between the standard deviations of BP on the last days of the control period and the carvedilol treatment. The difference between maximum and minimum BP during the day was not significant between the two periods. Circadian variations of heart rate were also not significantly different for the two periods. This indicates that carvedilol did not have any effect on circadian variations of BP and heart rate. The present study also suggests that low-dose carvedilol once daily may be effective in the treatment of hypertension.

Adrenergic beta-Antagonists↗
PubMed1987

Increase in plasma ouabainlike inhibitor of Na+, K+-ATPase with high sodium intake in patients with essential hypertension.

Changes in plasma levels of Na+, K+-ATPase inhibitors with salt loading were studied in eight patients with essential hypertension. By improving the assay method of Na+, K+-ATPase inhibitors to distinguish ouabain and vanadate, two types of inhibitors were detected in the plasma of patients with essential hypertension: One was ouabainlike and the other was nonouabainlike. The ouabainlike inhibitor was detected at low KCl concentrations (0.1 mM) in the assay buffer, and the nonouabainlike inhibitor was detected at a high KCl concentration (10 mM). By increasing dietary sodium chloride from 2 g/day for 5 days to 20 g/day for 6 days, systolic blood pressure increased significantly from 122 +/- 3.9 to 138 +/- 3.8 mmHg (p less than 0.005), whereas plasma renin activity decreased significantly from 3.9 +/- 0.8 to 0.8 +/- 0.3 ng/ml/hr (p less than 0.002). Under these conditions, the ouabainlike inhibitor increased significantly from 6.2 +/- 3.9% to 30.5 +/- 5.9% inhibition (p less than 0.005), after increasing dietary sodium. Furthermore, plasma level of the ouabainlike inhibitor correlated significantly with both systolic blood pressure (p less than 0.05) and daily urinary sodium excretion (p less than 0.01). In contrast, the plasma nonouabainlike inhibitor did not change with high sodium intake and did not correlate with blood pressure and daily urinary sodium excretion. These findings suggest that a ouabainlike inhibitor is involved in the maintenance of high blood pressure induced by high sodium intake in patients with essential hypertension. The role of the nonouabainlike inhibitor in blood pressure regulation is still unknown.

Blood Pressure↗
PubMed1987

[Diagnosis of adrenal medullary diseases in patients with sporadic or hereditary medullary thyroid carcinoma. A report of 37 cases with 8-year follow-up study].

Thirty-seven patients with medullary thyroid carcinoma were investigated to determine the status of adrenal medulla by computed tomography and 131I-metaiodobenzylguanidine (131I-MIBG) scintigraphy as well as measurements of urinary catecholamine excretion. Patients were followed up for 8 years in maximum. Fifteen patients belonged to multiple endocrine neoplasia type 2 including patients with incomplete phenotype. Computed tomography demonstrated adrenal tumors or enlargement in all 6 patients with urinary epinephrine (E) more than 30 micrograms/day, 4 of them were confirmed to have pheochromocytoma or adrenal medullary hyperplasia by surgery. In 2 patients with E less than 30 micrograms/day and epinephrine to norepinephrine (E/N) ratio more than 0.3 suggesting adrenal medullary hyperfunction, computed tomography revealed small adrenal tumors. Three of the remaining 7 patients with E less than 30 micrograms/day and E/N ratio less than 0.3 had equivocal enlargement of unilateral gland on computed tomography. 131I-MIBG scintigraphy demonstrated tracer uptake in adrenal glands with tumor more than 1cm in diameter. One of 2 adrenal glands with medullary hyperplasia showed a faint adrenal image on the scintiscan, but the other showed no tracer uptake. Pheochromocytoma became manifest in 4 patients during the follow-up period, 4, 13, 14 and 34 years after thyroid surgery. None of 22 patients with sporadic medullary thyroid carcinoma showed adrenal abnormalities on the examinations mentioned above.

Adrenal Gland Neoplasms↗
PubMed1987

Radioimmunoassay of atrial natriuretic polypeptide in heat-treated human plasma.

In this simple, sensitive radioimmunoassay (RIA) of atrial natriuretic polypeptide (hANP) in human plasma, nonspecific interference is minimized by deproteinizing the plasma by heat treatment at 85 degrees C for 10 min. We directly measure alpha-hANP in the supernates by RIA, with use of antiserum that recognizes the N-terminal region of alpha-hANP. The minimal detectable value was 0.4 pg per tube. The intra-assay CV was 6.6% (n = 8). The mean concentration of hANP in plasma of 54 healthy volunteers was 41 (SD 29) ng/L. Concentrations of hANP in plasma increased after saline infusion and high salt intake for one week in patients with essential hypertension. High concentrations were also measured in patients with renal failure and congestive heart failure. This method, which requires no extraction or purification with column chromatography, is especially useful for simultaneous measurement of several samples.

Atrial Natriuretic Factor↗
PubMed1987

The effect of reduced alcohol consumption on blood pressure: a randomised, controlled, single blind study.

A randomised, controlled, single blind trial was conducted in office workers with mild hypertension (systolic blood pressure (SBP) 140 to 180 mmHg, diastolic blood pressure (DBP) 90 to 110 mmHg) to determine the effect of decreasing alcohol consumption. After a baseline examination, 50 male volunteers aged 30 to 59 were randomised to two groups. Group A were told to abstain from or reduce alcohol consumption for two weeks, while group B were instructed to maintain their usual alcohol consumption. Complete records were obtained on 49 subjects. The daily alcohol consumption of groups A and B at baseline was similar, i.e. 71.9 ml and 72.5 ml of ethanol, respectively, and changed to 16.1 ml and 62.9 ml, respectively, during the experiment. After two weeks, group A were asked to resume their normal consumption whilst group B were asked to reduce or abstain (phase II). However in view of a treatment period interaction, statistical analysis was confined to phase I. During phase I, group A, whose alcohol consumption had reduced, showed decreases of 5.8 and 7.1 mmHg in SBP during the the first and second weeks, respectively. In group B, these decreases were only 0.6 and 1.9 mmHg, respectively. The difference between the falls in SBP in groups A and B was significant (P = 0.005) as judged by analysis of variance. The DBP also decreased, but there was no significant difference between the decreases in the two groups. Changes in gamma-glutamyl-transpeptidase, a biochemical marker of alcohol consumption, from the initial values to the end of phase I were significantly different in groups A and B.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1987

Extra-adrenal pheochromocytoma manifesting renovascular hypertension.

A case with extra-adrenal pheochromocytoma, which was found by chance in the course of renovascular hypertension, is reported. The tumor was on the stenotic portion of the right renal artery. The results of examinations for pheochromocytoma were not conclusive, that is, inconsistent elevation of plasma catecholamines and urinary catecholamine excretion, equivocal results of pharmacological tests for pheochromocytoma, and negative results in [131I]metaiodobenzylguanidine scintigraphy. The stenosis of the right renal artery disappeared, the blood pressure was normalized by surgical resection of the tumor, and the extra-adrenal pheochromocytoma was finally diagnosed by pathohistological findings. Renovascular hypertension appeared to be the primary cause of this hypertension, judging from the significant decrease in blood pressure induced by an angiotensin II analog and a renal vein renin ratio of 7.3. Even in the case of obvious renovascular hypertension, the possibility of this unusual coexistence with pheochromocytoma should be considered.

Adult↗
PubMed1986

Significant increase in plasma immunoreactive atrial natriuretic polypeptide concentration during head-out water immersion.

To investigate the physiological regulatory mechanism of human atrial natriuretic polypeptide (hANP) secretion, plasma hANP was measured by a direct radioimmunoassay during head-out total body water immersion (WI) in normal men. Five healthy men were immersed in water for 1 hr. Urine volume and Na excretion were significantly increased during WI. Plasma hANP increased significantly during WI peaking at 30 min. and returned toward the baseline after WI. Plasma renin activity and norepinephrine were suppressed occasionally during WI. Plasma ADH did not change throughout the study period. Maximal increments in plasma hANP correllated with that in urine output or urinary Na excretion during WI. These data suggest that acute central hypervolemia caused by WI increases hANP secretion and that this increase may participate in the diuretic response to WI.

Adrenal Cortex Hormones↗
PubMed1986

Circulating factor with ouabain-like immunoreactivity in patients with primary aldosteronism.

Circulating factor with ouabain-like immunoreactivity was studied in patients with primary aldosteronism. Anti-ouabain antibody was prepared from specific pathogen-free rabbits. In the plasma of patients with primary aldosteronism, the level of a factor with ouabain-like immunoreactivity was 2.59 +/- 1.39 pmol ouabain equivalent/ml plasma. This value was significantly (p less than 0.05) higher than that of age-matched normotensive subjects, 1.06 +/- 0.86 pmol ouabain equivalent/ml plasma. The plasma level of ouabain-like immunoreactivity correlated significantly (p less than 0.05) with blood pressure. These results indicate that the factor with ouabain-like immunoreactivity may play a pathophysiological role in the maintenance of the high blood pressure observed in patients with primary aldosteronism.

Antibody Affinity↗
PubMed1986

Metabolism of bradykinin in isolated perfused rat kidney. Measurement of kininase activity in perfusate and urine.

The effect of bradykinin and kininase on renal function and the metabolism of bradykinin in the kidney were examined in isolated perfused rat kidney. In this experimental system, exogenous bradykinin did not affect the water and electrolyte handling by the kidney. Most of bradykinin and kininase in urine were derived from kidney but not from circulating medium. Kininase II may not have a major role in bradykinin destruction by the kidney.

Animals↗
PubMed1986

Hutchinson-Gilford progeria syndrome in a 45-year-old man.

A 45-year-old man with typical Hutchinson-Gilford progeria syndrome is described. The patient had the characteristic physical findings of this syndrome, such as short stature, "horse-riding" stance, coxa valga, alopecia, micrognathia, craniofacial disproportion, and prominent eyes. He had refractory congestive heart failure due to arteriosclerotic heart disease and hypertension, and he also had arteriosclerosis obliterans. Some immunologic and endocrinologic abnormalities commonly seen in the elderly were present in this patient. On the basis of a review of the literature, this is the first patient with this syndrome who had survived into the fourth decade.

Arteriosclerosis Obliterans↗
PubMed1986

Changes in human plasma atrial natriuretic polypeptide concentration in normal subjects during passive leg raising and whole-body tilting.

The effect of central venous pressure on release of human atrial natriuretic polypeptide (hANP) was studied by measuring the plasma hANP levels during passive leg raising to 60 degrees and head up whole-body tilt at 60 degrees in normal volunteers. In ten subjects, after at least 1 h recumbency, both legs were raised passively 60 degrees for 20 min. While the legs were raised the plasma hANP level increased significantly from a basal level of 101 +/- 10 pg/ml (mean +/- SE) to a peak of 165 +/- 15 pg/ml after 10 min, and returned to the basal level 10 min after the legs were lowered. The blood pressure and pulse rate were not affected by raising the legs. The effect of head up whole-body tilt of 60 degrees from the supine position, for 20 min, was examined in nine normal subjects. Their plasma hANP decreased transiently at 5 min in five of them and at 10 min or later in the remaining four subjects. Their blood pressure did not change but their pulse rate increased significantly while their body was being tilted. These results suggest that secretion of hANP is regulated physiologically by changes in the central venous pressure.

Adult↗
PubMed1986

A case of adrenal tumor producing renin, aldosterone, and sex steroid hormones.

A 27-year-old woman with an adrenal tumor that produced renin and aldosterone, associated with hypertension and adrenogenital syndrome, is described. Severe hypertension, cardiomegaly, a low serum potassium level, clinical symptoms of adrenogenital syndrome, and a left upper abdominal tumor also were found. Endocrinological studies showed that plasma and urinary levels of sex steroid hormones such as dehydroepiandrosterone, androsterone, and testosterone were markedly increased. Plasma renin activity, plasma angiotensin II, and plasma aldosterone levels also were increased markedly, although deoxycorticosterone levels remained within the normal range. The possibility of renovascular hypertension was excluded by angiography of the renal artery and by venous sampling of plasma renin activity. Abnormal elevations in plasma aldosterone levels persisted despite normalization of plasma angiotensin II by converting enzyme inhibitor administration. It was suspected that this patient had an adrenal tumor producing renin as well as sex steroids and aldosterone. Microscopy of the resected tumor revealed that the tumor was composed mostly of cells with large nuclei and light cytoplasm. The tumor contained dehydroepiandrosterone, dehydroepiandrosterone sulfate, testosterone, aldosterone, and renin. Immunohistochemical study showed that some of the tumor cells produced renin. Biopsy of the left renal tissue showed evident atrophy of the juxtaglomerular cells and pronounced arteriosclerosis. After resection of the tumor, all blood and urinary levels of the abnormally increased hormones returned to a normal range and an apparent fall of blood pressure was noted. To our knowledge, this is the first report of a renin and aldosterone-producing adrenal tumor associated with hypertension and adrenogenital syndrome.

Adrenal Gland Neoplasms↗
PubMed1986

Radioimmunoassay of metanephrine and normetanephrine for diagnosis of pheochromocytoma.

Sensitive and specific radioimmunoassays of metanephrine and normetanephrine were developed by use of 125I-labeled synephrine and specific metanephrine antibody, and 125I-labeled octopamine and specific normetanephrine antibody. Specific antibody for both metanephrine and normetanephrine was raised in rabbits by immunization with bovine serum albumin conjugated with the corresponding hapten, prepared by the method of Grota and Brown (Endocrinology 1976;98:615). The detection limits of the metanephrine and the normetanephrine radioimmunoassays were 2 and 6 pg/tube, respectively. Mean plasma metanephrine and normetanephrine values for 24 normal subjects were 62 (SD 14) and 100 (SD 40) ng/L, respectively. Mean urinary metanephrine and normetanephrine values for 22 normal subjects were 154 (SD 74) and 217 (SD 109) micrograms/day. For 14 pheochromocytoma patients, plasma metanephrine and normetanephrine values ranged from 29 to 683 and from 28 to 7850 ng/L, and urinary metanephrine and normetanephrine values were 606 to 6630 and 296 to 4800 micrograms/day, respectively. The present methods are simple and suitable for routine tests or for mass screening for pheochromocytoma.

Adrenal Gland Neoplasms↗
PubMed1986

Hypotensive effect of long-term oral calcium supplementation in elderly patients with essential hypertension.

Calcium gluconate (22.4 g/day; 2 g/day as Ca) was administered orally for 8 weeks to eight hospitalized elderly patients with essential hypertension in order to confirm the hypotensive effect of oral calcium supplementation and to clarify its hypotensive mechanism by analyzing changes in hormonal factors. After 2 weeks of calcium supplementation, both systolic and diastolic pressures decreased significantly and remained decreased for the duration of the study. An elevation of plasma PGE2 correlated with blood pressure reduction was observed at 2 weeks. Plasma norepinephrine decreased significantly from 4 weeks. Plasma parathyroid hormone decreased significantly from 4 weeks, and 1,25-dihydroxyvitamin D (1,25-[OH]2D) decreased significantly at 8 weeks. The reduction of plasma 1,25-(OH)2D correlated with blood pressure decrease at 8 weeks. The present study indicates that the mechanism of its hypotensive effect is multifactorial and may be different during different phases of calcium supplementation. The suppression of plasma 1,25-(OH)2D following reduction of parathyroid hormone may be involved in the hypotensive effect in the chronic phase of calcium supplementation. Enhancement of PGE2 production in the early phase and suppression of sympathetic nervous activity in the chronic phase may also be factors in blood pressure reduction.

Administration, Oral↗