Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Human renin was purified from a juxtaglomerular cell tumor with a high renin content, 24.2 Goldblatt units/mg of protein. The purification procedure comprised three steps: gel filtration, DEAE-cellulose chromatography, and preparative isoelectric focusing. Five forms of renin amounting to 5.3 mg of enzyme were obtained with isoelectric points of 4.95, 5.10, 5.35, 5.55, and 5.70. They were all glycoproteins. The three major fractions had very similar specific activities, 868, 860, and 809 Goldblatt units/mg of protein. These fractions produced a single band on analytical isoelectric focusing and a single arc on immunoelectrophoresis. On polyacrylamide gel electrophoresis at pH 7.8, each fraction consisted of two renin bands with the same molecular weight, but different net charges. The molecular weight determined by gel filtration and Fergusson plot analysis on polyacrylamide gel was 38,000 to 42,000. The optimum pH determined on N-acetyltetradecapeptide substrate was 6.5, and the Km was 6.8 x 10(-6) M. These parameters were identical with those for standard human kidney renin. Antibodies raised against tumor renin completely inhibited the activity of both tumor and standard renin. Under dissociating conditions (sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel electrophoresis in the presence of 6 M urea), part of the purified enzyme dissociated into two smaller fragments (Mr = 20,000 and 25,000) containing renin activity.
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PMID:Multiple forms of human renin. Purification and characterization. 10 84

An unusual case of orbital tumor with high renin content and severe hypertension is described. The patient was a 15-year-old girl with juvenile hypertension (200-140 mmHg) associated with right exophthalmos and hypokalemia. The patient showed extremely high levels of plasma renin activity and plasma aldosterone concentration. No difference was present in plasma renin activity from either side of the renal veins. Preoperatively, hypertension responded to treatment with spironolactone. The tumor could not be completely removed because of intracranial metastasis and infiltration, and the hyperreninemia and secondary hyperaldosteronism persisted. The renin content in the orbital tissue was 1,403-2,225 ng/angiotensin I generated/h/g wet weight of tissue. The postmortem histopathologic diagnosis was orbital hemangiopericytoma. This is the first case of extrarenal (ectopic) renin-secreting (or -producing) hemangiopericytoma of the orbital origin. Furthermore this case is worthy of note in the point of view of the presence of the extrarenal renin-angiotensin system, particularly in the brain.
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PMID:A case of ectopic renin-secreting orbital hemangiopericytoma associated with juvenile hypertension and hypokalemia. 15 52

Big renin, a relatively inactive renin which possesses a molecular weight larger than that of normal plasma or renal renin, has been demonstrated by gel filtration in certain human plasma, tumor extracts, and amniotic fluid. Big renin was not present in normal plasma or kidney extracts. Plasma from 3 hypertensive patients with nephropathy contained chiefly big renin. Varying proportions of both big and normal renin activity were present in plasma of other patients with hypertension and proteinuria. The renin present in amniotic fluid, which increased in activity following exposure to acid pH, was shown to be big renin in two patients. Large amounts of circulating big renin apparently can cause hypertension in patients with Wilms' tumors. Furthermore, the relatively inactive big renin may replace normal plasma renin in some patients, resulting in low plasma renin activity.
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PMID:Occurrence of big renin in human plasma, amniotic fluid and kidney extracts. 16 87

A case of a young woman with the syndrome of primary aldosteronism and malignant ovarian tumor is reported. Hormone studies revealed extremely high urinary aldosterone, undetectable plasma renin activity, elevated plasma 17beta estradiol and testosterone, and low plasma FSH and LH. Plasma cortisol and urinary 17-hydroxycorticoids were at the upper normal limits. Autopsy disclosed an ovarian tumor, histologically an arrhenoblastoma, with polymorphic aspects. The adrenal glands grossly were normal. Aldosterone was found by the double radioisotopic technique in the neoplastic tissue.
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PMID:Primary aldosteronism due to a malignant ovarian tumor. 17 Dec 76

Plasma 16 beta-hydroxydehydroepiandrosterone (16 beta-OH-DHEA) levels were measured by radioimmunoassay in normal and pathological conditions in man. 16 beta-OH-DHEA levels in normal subjects rose sharply during adolescence and then declined slowly throughout adult life: 192 pg/ml age 7-11, 395 pg/ml age 15-19, 330 pg/ml age 20-39, 261 pg/ml age 40-59, and 124 pg/ml over 60-years-old. No marked difference was seen between male and female subjects. 16 beta OH-DHEA rose significantly (p less than .01) during adrenocorticotropin (ACTH) stimulation, declined (p less than .005) during dexamethasome suppression and during gonadal suppression, rose (p less than .05) during gonadal stimulation and following administration of WIN 24540, an inhibitor of 3 beta-o1-dehydrogenase (p less than .005). 16 beta-OH-DHEA levels in adrenal venous blood were higher than in inferior vena cava blood but the levels in hepatic venous blood were not higher than in arterial blood. These results indicate that 16 beta-OH-DHEA is secreted directly by the adrenal cortex and probably the gonads. 16 beta-OH-DHEA levels were elevated in normal pregnant women, pregnant women with toxemia and in patients with Cushing's disease, ectopic ACTH-producing tumor and congenital adrenal hyperplasia but not in patients with low-renin essential hypertension.
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PMID:Plasma 16 beta-hydroxydehydroepiandrosterone in normal and pathological conditions in man. 18 75

A 16-month-old black male infant had unusual thirst, polyuria, hyponatremia, and hypertension. His polyuria was unresponsive to vasopressin therapy, and his high blood pressure was not effectively controlled by antihypertensive drugs. Radiographic examinations revealed an occult Wilms tumor in the right kidney. After removal of the tumor, the signs and symptoms were relieved. The tumor had a renin activity about 280 times that of the adjacent renal cortex, and many intracytoplasmic secretory granules were found on electron microscopy. The pathogenesis of these clinical manifestations appears to be mediated through the physiologic pathways of renin-angiotensin II and renin-aldosterone.
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PMID:Polydipsia, polyuria, and hypertension associated with renin-secreting Wilms tumor. 20 43

The juxtaglomerular apparatus, located in the glomerular hilum, consists of a vascular component (afferent and efferent arterioles and extraglomerular mesangium) and a tubular component (macula densa). Two types of contact between vascular and tubular components are observed: a) a complex type, involving distal tubule, extraglomerular mesangium, and proximal efferent arteriole, and b) a simple type, consisting of apposition of the basement membranes of the vascular and tubular components. Juxtaglomerular granular cells, the source of renin, are present throughout the vascular component but are more numerous in the afferent arteriole. They can be considered as "myoendocrine" cells, since they contain myofibrils and attachment bodies, together with secretory granules and crystalline protogranules. Macula densa cells differ from those elsewhere in the distal tubule in that their nuclei are closer to each other, the Golgi apparatus is basally located, and their basal membrane infoldings are less prominent. Adrenergic nerves are demonstrable by fluorescence histochemistry in the juxtaglomerular region. Electron microscopy reveals unmyelinated nerve fibers containing small dense-cored vesicles and capable, as shown by ultrastructural autoradiography, of incorporating exogenous tritiated norepinephrine. Neuroeffector junctions occur between nerves and cells of the vascular and, less frequently, the tubular component. In addition, adrenergic axons are observed in a juxtaglomerular cell tumor. Nerve terminals are seen in direct contact with the tumor cells.
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PMID:Anatomy of the juxtaglomerular apparatus. 38 8

The time courses of change in renin activity after cold storage of human plasma at -5 degrees C and pH 7.4 were examined in 5 normal subjects, 6 patients with essential hypertension and one female patient with primary aldosteronism before and after extirpation of the adrenal tumor. In the 5 normal subjects and 6 essential hypertensives, the gradual increase in plasma renin activity was observed until 10 days of cold storage. The same result was obtained in the case of primary aldosteronism. However, there was no increase in renin activity despite of cold storage for 10 days in plasma which was sampled from this patient 45 days after operation. These data indicate that a period of 4 days for cryoactivation of human plasma renin as has been reported by Sealey et al. is not sufficient to accomplish activation of renin by cold storage.
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PMID:Change in plasma renin activity by cold storage of plasma in normal subjects and patients with essential hypertension and primary aldosteronism. 45 2

A case of renal rhabdomyosarcoma is presented. Besides the rarity of this tumor, the case is unique because an increased level of renin and hypertension was found, which was not due to compression of the main vessels.
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PMID:Hypertensive renal rhabdomyosarcoma. 46 74

Hypertension, hypokalemia, suppressed plasma renin activity and increased plasma aldosterone were found in a middle-aged woman. Following removal of the tumor in the left adrenal gland these abnormalities disappeared. Concurrently, however, the plasma cortisol level did not show normal diurnal change, although the value at 6 A.M. was within the normal range. Administration of 2 mg dexamethasone failed to depress the plasma cortisol level and urinary 17-OHCS concentrations. Postoperatively, plasma cortisol and urinary 17-OHCS were below normal. Histologic examination of the tumor indicated the presence of two types of adenoma cells; one was a large watery clear cell with rich lipid and possibly with aldosterone secretion and the other was an acidophilic cell with poor lipid and possibly with cortisol secretion. It is suggested that, in addition to oversecretion of aldosterone, the tumor autonomously secreted cortisol, although the amount of cortisol secreted was not large enough to produce typical Cushing's syndrome.
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PMID:Concurrent hypersecretion of aldosterone and cortisol from the adrenal cortical adenoma. 47 99


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