Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Chromogranin A expression is heritable in humans, and both plasma chromogranin A concentration and its releasable adrenal and sympathetic neuronal pools are augmented in established essential (hereditary) hypertension. To evaluate chromogranin A further as a simpler or "intermediate phenotype" in the complex trait of hypertension, we studied chromogranin A expression in the spontaneously hypertensive rat (SHR), a rodent model of essential hypertension. Both plasma (p < 0.0001) and adrenal medullary (p = 0.003 to p < 0.0001) chromogranin A were elevated in the SHR, even at the earliest stages (3-4 weeks of age). In the adult adrenal gland, both chromogranin A (p=0.005) and norepinephrine (p=0.011) were increased in the SHR, while dopamine beta-hydroxylase activity was diminished (p < 0.0001). Chromogranin A mRNA expression was also elevated in the SHR adrenal medulla (p = 0.017). Differences in chromogranin A processing were not noted between SHR and Wistar Kyoto control (WKY) rats. In an SHR x WKY genetic intercross, control of the adrenal chromogranin A phenotype by a single major locus was suggested by comparison of phenotypic variance of the F2 vs F1 generations, and by bimodal frequency histogram (3:1 ratio), confirmed by maximum likelihood analysis (chi2 = 74.6, p < 0.000001) in the F2 generation. However, microsatellite alleles at a surrogate locus (Ighe) 12.7 cM from chromogranin A (Chga), on rat chromosome 6, failed to co-segregate with blood pressure in an F2 generation (F = 0.06, p = 0.94). In another rodent model of hereditary hypertension, the genetically hypertensive mouse (BPH/2), adrenal chromogranin A (p=0.018) and norepinephrine (p = 0.004) were actually diminished. We conclude that over-expression of chromogranin A is a variable feature of mammalian genetic hypertension. In one rodent model (the SHR), over-expression of chromogranin A is largely controlled by a single genetic locus, but the chromogranin A locus itself is not directly linked to determination of the blood pressure elevation of the SHR.
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PMID:Catecholamine storage vesicle protein expression in genetic hypertension. 1080 89

The aim of the study was to define features indicating malignancy in pheochromocytoma through analysis of clinical data, immunomorphological and nuclear DNA ploidy patterns with flow cytometry. The studied group consisted of 33 patients with hypertension and adrenal gland tumor. In all patients 24 hr measurements of adrenaline, noradrenaline, dopamine and their metabolites were taken and the content of these substances in the tumor tissue was measured. Morphologically most pheochromocytomas displayed alveolar pattern with polyhedral cells with clear cytoplasm. Nuclear pleomorphism was infrequent and mitotic figures were rare. In 5 tumors areas of ganglioneuromatous differentiation were present with neurofilament expression. Morphological features indicating malignancy were noted--vascular emboli of tumor cells, capsular infiltration and foci of necrosis. However, in the patient with metastases evident during operation, none of those features was found in the tumor sample. All pheochromocytomas expressed neuroendocrine markers (chromogranin A, synaptophysin and NSE) and most also vimentin. Reactivity of other markers was negligible. In DNA ploidy studies in 22/33 cases there was DNA diploid (normal) pattern. The patient with metastases belonged to this group. In 3 cases there were aneuploid tumor cells on histograms and in 8 increased number of tetraploid cells. The follow-up period of our patients was 1-43 months.
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PMID:Immunomorphological studies and cytometric DNA ploidy in diagnostics of pheochromocytoma. 1097 31

Chromaffin granule transmitters such as chromogranin A and catecholamines have been used in the diagnosis of pheochromocytoma, but the diagnostic and prognostic value of chromogranin A have not been explored in malignant pheochromocytoma. We evaluated these transmitters in patients with pheochromocytoma (n=27), both benign (n=13) and malignant (n=14). Patients with benign pheochromocytoma were studied before and after surgical excision (n=6), whereas patients with malignant pheochromocytoma were evaluated before and after combination chemotherapy with regular cycles of cyclophosphamide/dacarbazine/vincristine (nonrandomized trial in n=9). During treatment, patient responses to chemotherapy were divided according to anatomic and clinical criteria: responders (n=5) versus nonresponders (n=4). Plasma chromogranin A rose progressively (P<0.0001) from control subjects (48.0+/-3.0 ng/mL) to benign pheochromocytoma (188+/-40.5 ng/mL) to malignant pheochromocytoma (2932+/-960 ng/mL). Parallel changes were seen for plasma norepinephrine (P<0.0001), though plasma epinephrine was actually lower in malignant than benign pheochromocytoma (P=0.0182). In bivariate analyses, chromogranin A, norepinephrine, and epinephrine discriminated between pheochromocytoma and control subjects (all P<0.0001), whereas in a multivariate analyses, norepinephrine was the best discriminator (P:=0.011). Chromogranin A was significantly different in benign versus malignant pheochromocytoma on both bivariate (P=0.0003) and multivariate (P:=0.011) analyses. After excision of benign pheochromocytoma, chromogranin A (P=0.028), norepinephrine (P=0.047), and epinephrine (P=0.037) all fell to values near normal. During chemotherapy of malignant pheochromocytoma (n=9), plasma chromogranin A (P=0.047) and norepinephrine (P=0.02) fell but not epinephrine. In 5 responders to chemotherapy, there were significant declines in chromogranin A (P=0.03) and norepinephrine (P=0.03) but not epinephrine; in 4 nonresponders, none of the transmitters changed. Plasma chromogranin A varied longitudinally with tumor response and relapse. We conclude that plasma chromogranin A is an effective tool in the diagnosis of pheochromocytoma, and markedly elevated chromogranin A may point to malignant pheochromocytoma. During chemotherapy of malignant pheochromocytoma, chromogranin A can be used to gauge tumor response and relapse.
Hypertension 2000 Dec
PMID:Malignant pheochromocytoma. Chromaffin granule transmitters and response to treatment. 1111 23

Serum chromogranin A (CgA) is a useful marker for neuroendocrine tumors and is detectable in carcinomas at advanced stages. Elevated serum CgA is also an indicator of poor prognosis in prostate cancer and is useful for predicting the failure of hormonal therapy for prostate cancer patients. We found that CgA molecules with three different sizes could be detected in normal human serum. However, only the largest CgA molecule appears in patients with liver disease. Serum taken from cancer patients is composed predominantly of the middle-sized molecule, whereas the smallest CgA molecule was elevated in serum drawn from renal patients. Moreover, only the smallest CgA molecule was found in urine. We believe that the largest CgA molecule is metabolized by the liver, whereas the smallest CgA molecule is removed from the blood circulation via the kidney. Because the medium-sized CgA is the dominant molecule in both the cell medium of the tumor cell line SK-N-AS and sera from patients with malignant diseases, CgA from the cell medium was selected as the calibrator for the CgA ELISA assay. Our findings also suggest that it would not be possible to measure the urinary CgA to reflect the serum CgA concentration in order to detect pheochromocytoma among patients with hypertension.
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PMID:Characterization of serum and urinary chromogranin A by size exclusion chromatography: impact on calibrator selection and urinary assay. 1143 2

A 52-yr-old woman presented with hypertension, elevated urinary vanillylmandelic acid, metanephrines, normetanephrines, and plasma chromogranin A (CgA), but normal urinary catecholamine levels. Abdominal ultrasonography and subsequent MRI imaging showed a 3 cm nodular lesion of the right adrenal gland also visualized by 123I-meta-iodobenzylguanidine scintigraphy consistent with a pheochromocytoma (PC). Her OctreoScan was negative. The patient underwent right adrenalectomy and histological examination showed a PC. The adrenal medulla tissue was examined for somatostatin (SRIH) receptor subtypes 1 to 5 (SSTR1 to 5) expression by RT-PCR. Cultured tumor cells were treated with either SRIH, Lanreotide (Lan), or an SSTR2 (BIM-23 120) or SSTR5 (BIM-23 206) selective agonist. CgA secretion was measured in the medium by ELISA and catecholamine levels by HPLC after 6h. Cell viability was assessed after 48h. RT-PCR analysis showed that SSTR1, 2, 3 and 4 were expressed. CgA secretion was significantly reduced by SRIH (- 80 %), Lan (- 35 %), and the SSTR2 selective agonist (- 65 %). Norepinephrine secretion was reduced by SRIH (- 66 %), Lan (- 40 %), and BIM-23 120 (- 70 %). Epinephrine and dopamine secretion was also inhibited by treatment with SRIH (- 90 % and - 93 %, respectively) and BIM-23 120 (- 33 % and - 75 %, respectively) but not by Lan. Cell viability was also significantly reduced by SRIH (- 30 %), Lan (- 10 %), and the SSTR2 selective agonist (- 20 %). The SSTR5 selective agonist did not modify either CgA and catecholamine secretion or cell viability. Our data show that SSTRs may be present in a PC although OctreoScan is negative in vivo, and that SRIH and its analogs may reduce both differentiated and proliferative functions in chromaffin cells in vitro. These findings suggest that SRIH analogs with enhanced SSTR2 affinity might be useful in the medical therapy of PC, even when an OctreoScan is negative.
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PMID:An in vivo OctreoScan-negative adrenal pheochromocytoma expresses somatostatin receptors and responds to somatostatin analogs treatment in vitro. 1292 Jun 56

We report a potential pitfall of 123I-metaiodobenzylguanine (MIBG) scan. Magnetic resonance imaging performed for other reasons, showed 2.5 cm tumor in the left adrenal gland. On questioning patient had episodic palpitations, flushing and hypertension suggestive of pheochromocytoma. Urinary metanephrine level was of borderline value but serum chromogranin A level was clearly elevated. 123I-MIBG scan showed accumulation of the tracer in the upper left abdomen and the finding was suspected to be intra-adrenal pheochromocytoma. During operation two separate tumors, adrenocortical adenoma in the left adrenal gland, and another smaller, extra-adrenal paraganglioma locating very close to the adenoma, were found. Thus the positive MIBG finding was caused by a paraganglioma with the concurrent presentation of nonfunctioning adrenocortical adenoma.
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PMID:A pitfall of metaiodobenzylguanidine scan: paraganglioma in close proximity to adrenocortical adenoma. 1295 37

We describe a case of primary pulmonary paraganglioma, a tumor that has not been reported in sufficient detail in previous literature. The patient was a 55-year-old woman with hypertension accompanied by an elevated serum norepinephrine level (2651 pg/mL; normal 100-450 pg/mL). Computed tomography revealed a well-circumscribed solid mass, 3.5 cm in diameter, located in the lower lobe of the left lung. In the lobectomy specimen, the tumor had invaded the B8 bronchus and hilar lymph nodes with microscopic metastasis to the mediastinal nodes. The tumor showed histologic, immunohistochemical, and ultrastructural features of paraganglioma: argyrophilic cells arranged in a nesting (Zellballen) or anastomosing trabecular pattern within an arcuate vascular network. Neoplastic chief cells positive for neuroendocrine markers (CD56, synaptophysin, chromogranin A) were surrounded by sustentacular cells positive for S-100 protein. Neurofilament protein was positively stained, but cytokeratins were totally negative. On electron microscopy, chief cells possessed abundant dense core granules with an eccentric halo ("norepinephrine-type" granules). The patient's blood pressure began to decline soon after the resection, and her serum norepinephrine promptly returned to almost normal. On the basis of our experience, our case is a bona fide primary pulmonary paraganglioma, a tumor heretofore subject to considerable skepticism.
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PMID:Primary pulmonary paraganglioma: report of a functioning case with immunohistochemical and ultrastructural study. 1516 77

We report the case of a 52-yr-old man with a mass in the area of the left adrenal. The clinical features, MIBG uptake, and elevated urinary dopamine levels suggested the diagnosis of pheochromocytoma. He presented with unstable hypertension, tachycardia, weight loss, and the "inflammatory syndrome" (fever, leukocytosis, and high sedimentation rate). Clinical findings, preoperative radiographic (sonography, CT scan, [131I]MIBG scintigraphy), and endocrine evaluations (elevated 24-h urinary dopamine) were suggestive of a dopamine-secreting adrenal tumor. The mass was resected and on histologic examination showed the characteristic features of a malignant fibrous histiocytoma (MFH). The tumor cells were immunopositive for neuron-specific enolase (NSE), vimentin, CD-68, S-100, desmin, and immunonegative for chromogranin A, synaptophysin, neurofilament protein, and low-molecular-weight keratin, indicating that this tumor was not able to synthesize catecholamines. The prolonged retention of the tracer (MIBG) was interpreted as a consequence of obstructive hydronephrosis, while elevated urinary dopamine levels were assumed to be due to compression of the renal vessels by the large retroperitoneal mass.
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PMID:Retroperitoneal malignant fibrous histiocytoma mimicking pheochromocytoma. 1524 9

The secretory prohormone chromogranin A (CHGA) is overexpressed in essential hypertension, a complex trait with genetic predisposition, while its catecholamine release-inhibitory fragment catestatin is diminished, and low catestatin predicts augmented adrenergic pressor responses. These findings from studies on humans suggest a mechanism whereby diminished catestatin might increase the risk for hypertension. We generated Chga and humanized mice through transgenic insertion of a human CHGA haplotype in order to probe CHGA and catestatin in vivo. Chga mice displayed extreme phenotypic changes, including: (a) decreased chromaffin granule size and number; (b) elevated BP; (c) loss of diurnal BP variation; (d) increased left ventricular mass and cavity dimensions; (e) decreased adrenal catecholamine, neuropeptide Y (Npy), and ATP contents; (f) increased catecholamine/ATP ratio in the chromaffin granule; and (g) increased plasma catecholamine and Npy levels. Rescue of elevated BP to normalcy was achieved by either exogenous catestatin replacement or humanization of Chga mice. Loss of the physiological "brake" catestatin in Chga mice coupled with dysregulation of transmitter storage and release may act in concert to alter autonomic control of the circulation in vivo, eventuating in hypertension.
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PMID:Hypertension from targeted ablation of chromogranin A can be rescued by the human ortholog. 1600 50

A 63-year-old male patient was admitted for the treatment of malignant pheochromocytoma with multiple liver metastases. Plasma and urinary levels of catecholamines were elevated. Transcatheter arterial embolization (TAE) with concomitant administration of mitomycin C and gelatin sponge was performed for the treatment of liver metastases. Dose of alpha-1 blocker before TAE was increased to prevent hypertensive crisis during and after TAE. The hepatic metastatic lesion of CT findings was decreased after TAE. Although blood pressure showed a transient hypertension (180/100 mmHg) after every TAE, it returned rapidly to normal. The patient experienced transient abdominal pain, nausea, and loss of appetite after every TAE; however, those symptoms were readily controlled by conventional medications. Slight elevation of liver transaminases was recognized but returned to normal range within 3 weeks. No other major side effects were seen with TAE. While plasma and urinary level of catecholamines were unchanged, plasma chromogranin A (CgA) level was significantly decreased. These results suggest that TAE is a useful treatment for hepatic metastases. Plasma CgA level is a useful marker in the treatment of malignant pheochromocytoma.
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PMID:Transcatheter arterial embolization for the treatment of liver metastases in a patient with malignant pheochromocytoma. 1654 73


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