Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0001430 (adenoma)
 21,222 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Endothelin-1 (ET-1) receptors of normal adrenal gland (ADR, 6 cases), aldosterone-producing adenoma (APA, 5 cases), idiopathic hyperaldosteronism (IHA, 4 cases) and pheochromocytoma (PHE, 6 cases) in human were measured by radioligand binding assay (RBA) of receptors. Binding studies using 125I-ET-1 as a radio ligand showed the presence of a single class of high-affinity binding sites for ET-1 in all of the above tissues. The values of dissociation constant (Kd) of ET-1 for its receptor were similar in ADR, APA and IHA (28.3 +/- 2.5, 27.9 +/- 6.1, 27.7 +/- 1.9 pmol/L, respectively), but the maximal binding capacity (Bmax) of ET receptor tended to be lower in APA tissue (107.2 +/- 13.2 fmol/mg protein) in comparison with ADR (P < 0.01) and IHA (P < 0.05, 274.9 +/- 40.8, 247.0 +/- 19.8 fmol/mg protein, respectively). Both the Kd (50.8 +/- 5.1 pmol/L) and Bmax (675.3 +/- 93.7 fmol/mg protein) in PHE were higher than those in ADR (P < 0.01), APA (P < 0.01) or IHA (P < 0.05 for Kd, P < 0.01 for Bmax). Our data may suggest that there is the down-regulation for ET-1 receptor in APA and support the concept of an important role of ET-1 in the paracrine-autocrine regulation of aldosterone and catecholamine secretion in the adrenal and adrenal tumors.
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PMID:[Endothelin-1 receptors of the normal adrenal gland and adrenal tumors in human]. 959 18

To elucidate the presence and distribution of Endothelin-1 (ET-1) in tissues of human salivary glands, we performed an immunohistochemical analysis of ET-1 in 15 normal salivary glands, 8 adenolymphomas, 13 pleomorphic adenomas and 5 carcinomas, using the mouse monoclonal antibody against human ET-1. In normal glands, immunoreactivity for ET-1 was observed in the striated duct cells. In adenolymphomas, the columnar cells of the granular epithelium showed strong intracytoplasmic immunoreactivity. In carcinomas, moderate or strong immunoreactivity was observed in the tumor cells, whereas in pleomorphic adenomas, weak immunoreactivity was observed. A good relation was detected between the size of pleomorphic adenoma and ET-1 immunoreactivity, as well as between the duration of tumor in carcinoma and ET-1 immunoreactivity. The presence and distribution of ET-1 in salivary glands and salivary gland tumors suggests a possible role for ET-1 in the regulation of electrolytes and water transport in salivary glands, and as a growth-promoting factor for tumors.
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PMID:Presence of endothelin-1 in human salivary glands and tumors. 989 50

Endothelin-1 (ET-1) could play a role in the regulation of aldosterone secretion of the human adrenal gland. The presence of the endothelin-converting enzyme 1 (ECE-1) and ET-1 suggests that there is a local ET system in the adrenal cortex, but the in situ synthesis of ET-1 remains to be confirmed. The cellular distribution of the whole ET system was evaluated in 20 cases of aldosterone-producing adenomas. Polymerase chain reaction studies gave strong signals for ECE-1 mRNA and the mRNAs for endothelin type A (ET(A)) and B (ET(B)) receptors and faint signals for prepro-ET-1 mRNA. In situ hybridization showed ET(A) receptors scattered throughout the adenoma, in both secretory cells and vascular structures (score, +). There were more ET(B) receptors (score, ++), but they were restricted mainly to the endothelium. ECE-1 mRNA and protein were ubiquitous and abundant in secretory cells (score, +++) and vascular structures (score, ++); the enzyme was active on big ET-1. There was no prepro-ET-1 mRNA in the cortex, except in the thickened precapillary arterioles present in only 30% of the aldosterone-producing adenomas studied. ET-1 immunoreactivity was detected in vascular structures (score, +), probably bound to receptors, suggesting that ET-1 has an endocrine action. The low concentrations of ET-1 could also indicate that it acts in a paracrine-autocrine fashion to control adrenal blood flow. The discrepancy between the concentrations of ECE-1 and its substrate suggests that ECE-1 has another role in the adrenal secretory cells. Our data indicate that ET probably is not a primary cause of the development or maintenance of the adenoma.
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PMID:Localization of the endothelin system in aldosterone-producing adenomas. 1171 11

The results of the Randomized Aldactone Evaluation Study (RALES) and of several experimental studies have indicated that excess aldosterone detrimentally affects cardiovascular morbidity and mortality by acting through both classical and non-classical mineralocorticoid receptors. The effects mediated through classical mineralocorticoid receptors entail enhanced sodium and water reabsorption, potassium loss and hypokalaemia, congestion, increased vascular resistance and hypertension. Those occurring through non-classical mineralocorticoid receptors located on myofibroblasts comprise cardiac hypertrophy and fibrosis, which may be due to a direct effect of aldosterone on collagen synthesis. Data obtained in primary aldosteronism patients demonstrated left ventricular hypertrophy, as well as changes in left ventricular filling that can be accounted for by cardiac fibrosis. Available clinical data indicate that in a considerable proportion of congestive heart failure (CHF) patients treated with angiotensin converting enzyme (ACE) inhibitors, aldosterone secretion can escape from blockade of the renin-angiotensin system, thus suggesting that additional mechanisms, besides angiotensin II, can play an important role in the regulation of aldosterone secretion. Compelling evidence indicates that endothelin (ET)-1 is overtly increased in severe CHF and thus is a likely candidate for the aldosterone 'escape' phenomenon in CHF. Endothelin-1 is expressed in the adrenal cortex, together with its receptor subtypes A (ETA) and B (ETB), and directly stimulates aldosterone secretion in different species, in humans by acting via both ETA and ETB receptor subtypes. Moreover, we have recently found that the novel endothelin peptide ET-1 (1-31), by acting as an ETA agonist, can also be involved in the regulation of growth of the adrenal cortex, as well as in the pathogenesis of Conn's adenoma. In this paper, we review the findings suggesting a relationship between activation of the ET-1 system, enhanced aldosterone secretion and cardiac fibrosis and discuss the implications of endothelin antagonism for cardiovascular disease.
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PMID:The endothelin-aldosterone axis and cardiovascular diseases. 1181 78