Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0221002 (primary hyperparathyroidism)
 4,921 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Chromogranin-A (CgA), also termed secretory protein-I, is an acidic glycoprotein that is synthesized and secreted by cells of the diffuse endocrine and neuroendocrine system. Several previous studies had suggested that plasma levels of CgA were elevated in patients with primary hyperparathyroidism. In the present study we sought to examine expression of the CgA gene in human parathyroid tissue from patients with primary hyperparathyroidism. We characterized the mRNAs coding for CgA and beta-actin in parathyroid tissue fragments obtained from 12 patients with parathyroid adenomas, 11 patients with familial multiple endocrine neoplasia type I (FMEN I) with parathyroid hyperplasia, and 11 normal subjects. The mRNAs were detected and analyzed by dot and Northern blot hybridization using cDNA probes. CgA mRNA transcripts of 2.1 kilobases were detected in normal and pathological parathyroids. Similarly, beta-actin mRNA species of 2.1 kilobases was present in all tissues. The relative level of parathyroid tissue CgA mRNA, calculated as the CgA/beta-actin mRNA ratio, was 73 +/- 18 in parathyroid adenoma, 73 +/- 20 in FMEN I, and 100 +/- 9 in controls (mean +/- SE; expressed as a percentage of the control reference group value). There were no significant differences among the steady state levels of CgA mRNA levels in these three groups (F = 0.98; P = 0.39). These results demonstrate that expression of CgA mRNA is qualitatively and quantitatively normal in parathyroid tumors from patients with FMEN I and parathyroid adenoma.
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PMID:Expression of chromogranin-A messenger ribonucleic acid in parathyroid tissue from patients with primary hyperparathyroidism. 234

Serum levels of parathyroid hormone (PTH), alkaline phosphatase (ALP), calcium, creatinine, and vitamin D and the glomerular filtration rate were compared with the histologic properties and expression of PTH and chromogranin A in excised parathyroid adenomas from patients with primary hyperparathyroidism (pHPT). PTH and chromogranin A were detected immunohistochemically, and their mRNA was demonstrated by in situ hybridization with quantification of their mRNA levels by image analysis. There was a positive correlation between the cellular levels of PTH mRNA and the cellular levels of chromogranin A mRNA (r = 4.4; p < 0.05). However, within certain parts of the adenomas, mostly consisting of chief cells, the expression of PTH mRNA and chromogranin A mRNA was heterogeneous and the levels did not correspond to each other. A reduced suppressibility of PTH in patients with pHPT was confirmed. Although cellular levels of PTH and chromogranin A and their mRNAs were low in the oxyphilic parts of the adenomas, there was no correlation between the amount of oxyphilic cells in the adenomas and the suppressibility of PTH by calcium. There was also no association between the cellular levels of PTH mRNA or chromogranin A mRNA as studied by image analysis and "calcium sensitivity." Our results thus demonstrate that although PTH and chromogranin A mRNA levels are in general correlated to each other there are differences in their expression within and between individual parathyroid adenomas. It therefore seems likely that the expression of PTH and chromogranin A are differentially regulated, and that PTH and chromogranin A may not always be co-secreted. This point could be of importance, as chromogranin A and its cleavage products are known to influence PTH secretion.
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PMID:Parathyroid function and histology in patients with parathyroid adenoma: correlation of clinical and morphologic findings. 920 47

Pancreastatin, a C-terminally amidated peptide derived from chromogranin A, is known to inhibit insulin secretion, pancreatic enzyme release, and gastric acid secretion. It also inhibits parathyroid hormone (PTH) secretion in animals. The physiologic and clinical relevance of pancreastatin in humans, however, is not known. Because pancreastatin has been found in parathyroid adenomas, we investigated the plasma levels in patients with primary hyperparathyroidism (pHPT). Thirteen patients operated on for solitary parathyroid adenoma were investigated. Plasma levels of pancreastatin and serum levels of ionized calcium and intact PTH were measured before and 6 weeks after operation. In 10 patients the levels were also monitored before and 60 minutes after adenoma excision. The adenomas were investigated for pancreastatin immunoreactivity by immunocytochemistry. The median weight of the excised parathyroid adenoma was 0.64 g (range 0.07-2.00 g). Cells displaying pancreastatin immunoreactivity were present in all adenomas examined and varied in number and immunostaining intensity among and within the adenomas. Intraoperatively, after adenoma excision the levels of PTH and pancreastatin declined (p < 0.01), whereas the levels of ionized calcium did not change (p = 0.96). At the 6-week follow-up the levels of ionized calcium and PTH had decreased compared to the preoperative levels (p < 0.01), and all patients were normocalcemic. In contrast, the pancreastatin levels were not changed (14.5 +/- 6.1 pmol/L preoperatively vs. 12.8 +/- 11.2 pmol/L 6 weeks postoperatively; p = 0.12). In patients with pHPT, pancreastatin is likely to be produced by the parathyroid adenoma. The changes in pancreastatin levels immediately after surgery warrant further investigation.
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PMID:Pancreastatin plasma levels in patients with primary hyperparathyroidism. 1119 27

MEN 1 syndrome (Multiple Endocrine Neoplasia type 1) is a rare endocrine disorder characterized by the association of tumors in several endocrine glands, mainly in parathyroids, gut and pituitary. At our institution in the years 1982-2004 we have followed 26 patients with MEN 1 syndrome belonging to 19 families. The diagnosis of MEN 1 was based on Gubbio Consensus (JCEM 86: 5658-5671, 2001). Mean age at the diagnosis of MEN 1 was 35 years. Primary hyperparathyroidism was the most frequent pathology, which was diagnosed in 25 of 26 patients (96%). Gut endocrine tumors were found in 20 patients (77%), while pituitary tumors in 18 (70%). Non-functioning gut tumors were most frequent (n=9), followed by insulinoma (n=7) and gastrinoma (n=4). Prolactinoma was the most frequent pituitary tumor found in 12 patients (67%). Three patients died during the observation period - all of them of generalized gut endocrine tumor (gastrinoma in 2 cases and foregut carcinoid in one case). The management of MEN 1 is not easy and careful analysis of clinical picture is necessary in each individual case. Several important observations can be made on the basis of own experience and the literature: 1. In each sporadic pathology, which may be a part of MEN 1, one should consider. the possibility of MEN 1. The individual MEN 1 abnormalities are often diagnosed after 40 and later 2. MEN 1 tumor are usually multiple thus necessitating a different therapeutic approach (more radical surgery) 3. The most valuable screening tests are: Ca++, PP, CgA and prolactin 4. Endoscopic ultrasound is the most specific method for the localization of pancreatic endocrine tumors. 5. The results of surgical treatment of MEN 1 tumors are worse than that of sporadic tumors. 6. Prognosis in MEN 1 is determined by the behaviour of gut neuroendocrine tumor 7. No genotype/phenotype correlation in MEN 1 syndrome was found so far. In summary, it should be underlined that MEN 1 syndrome is an endocrine disorder, in which early diagnosis and optimal treatment may significantly improve the prognosis.
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PMID:[Diagnostic and therapeutic difficulties in MEN 1 syndrome]. 1635 Jul 23

We are reporting a case of a capillary haemangioma-like proliferation arising within a parathyroid gland adenoma, associated with primary hyperparathyroidism. The vessel proliferation bearing a close resemblance to a capillary haemangioma consisted of tightly packed capillaries, endothelial buds and occasional small caliber muscle-containing vessels. The observation expands the spectrum of tumour-associated vascular proliferations by adding an exuberant haemangioma-like pattern to its extreme end. These are a heterogeneous group of lesions reportedly induced by aberrant production of angiogenic factors. We investigated expression of VEGF, pKDR, FGF2, HIF1alpha and HIF2alpha and only VEGF gave a strong positive reaction in the adenoma cells entrapped in the vascular meshwork. Although this does not constitute a proof that aberrant VEGF production was a causative agent, unexpected supportive evidence for its pathogenic role emerged from a failure to detect chromogranin A. Chromogranin A is a precursor of several regulatory proteins, including vasostatin I, a multilevel suppressor of VEGF. The production of vasostatin I may have been reduced in a chromogranin A-negative adenoma which could lead to a loss of its opposing effect on VEGF-regulated processes. The only two other published cases of haemangioma of the parathyroid gland were reported in patients diagnosed with primary parathyroid hyperplasia with hyperparathyroidism, a pathophysiologic condition similar to our case. Therefore we raise the question whether these tumours could also represent a reactive phenomenon.
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PMID:Haemangioma of the parathyroid gland. Does it really exist? 2006 87