[Expression of urotensin II and G-protein coupled receptor 14 mRNA in human pheochromocytoma tissues].
ABSTRACT To investigate the expression of urotensin II (U II) and G-protein coupled receptor 14 (GPR14) mRNA in human pheochromocytoma tissues.
Total RNA from normal adrenal and pheochromocytoma tissues was extracted. The reverse transcription-polymerase chain reaction method was used to evaluate the levels of U II and GPR14 mRNA expression in human pheochromocytoma tissues.
There was no significant difference of U II and GPR14 mRNA expression between normal adrenal cortex and medulla. The expression of U II and GPR14 mRNA in pheochromocytoma was significantly lower than that in normal adrenal cortex and medulla (P < 0.05). The expression of GPR14 mRNA in adrenal pheochromocytomas was significantly lower than that of extra-adrenal pheochromocytomas (P < 0.05).
U II and GPR14 may play a role in the pathogenesis and hypertension regulating of pheochromocytoma.
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ABSTRACT: Hypertension is a well-known risk factor for atherosclerosis, but the molecular mechanisms that link elevated blood pressure to the progression of atherosclerosis remain unclear. Human urotensin II (U-II), the most potent endogenous vasoconstrictor peptide identified to date, and its receptor (UT receptor) are involved in the etiology of essential hypertension. In patients with essential hypertension, U-II infused into the forearm brachial artery has been shown to induce vasoconstriction. Recent studies have demonstrated elevated plasma U-II concentrations in patients with essential hypertension, diabetes mellitus, atherosclerosis, and coronary artery disease. U-II is expressed in endothelial cells, macrophages, macrophage-derived foam cells, and myointimal and medial vascular smooth muscle cells (VSMCs) of atherosclerotic human coronary arteries. UT receptors are present in VSMCs of human coronary arteries, the thoracic aorta and cardiac myocytes. Lymphocytes are the most active producers of U-II, whereas monocytes and macrophages are the major cell types expressing UT receptors, with relatively little receptor expression in foam cells, lymphocytes, and platelets. U-II accelerates foam cell formation by up-regulation of acyl-coenzyme A:cholesterol acyltransferase-1 in human monocyte-derived macrophages. In human endothelial cells, U-II promotes cell proliferation and up-regulates type 1 collagen expression. U-II also activates nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and plasminogen activator inhibitor-1 in human VSMCs, and stimulates VSMC proliferation with synergistic effects observed when combined with oxidized low-density lipoprotein, lysophosphatidylcholine, reactive oxygen species or serotonin. These findings suggest that U-II plays key roles in accelerating the development of atherosclerosis, thereby leading to coronary artery disease.Hypertension Research 07/2006; 29(6):375-87. · 2.94 Impact Factor