Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P41181 (collecting duct)
 5,183 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Adrenomedullin (ADM) is a newly described 52-amino acid peptide originally isolated from extracts of human pheochromocytoma and, more recently, detected in human plasma. Based on the report that ADM mRNA and immunoreactivity are present in the kidney, the current study was designed to determine the renal distribution of ADM by immunohistochemistry and the renal biological actions of ADM. In the immunohistochemical studies, the present investigation demonstrated the localization of ADM in glomeruli, cortical distal tubules, and medullary collecting duct cells of the normal canine kidney. In the in vivo studies, ADM was administered (0.25 ng.kg-1.min-1 in group I and 1, 5, and 25 ng.kg-1.min-1 in group II) intrarenally in normal mongrel dogs with the contralateral kidney receiving only saline vehicle. Intrarenal infusion of ADM resulted in a marked diuretic and natriuretic response, whereas the contralateral kidney showed no renal effects. These significant natriuresis and diuresis in the ADM kidney were associated with increases in glomerular filtration rate and fractional sodium excretion and with a decrease in distal tubular sodium reabsorption. Intrarenal infusion of ADM also caused an increase in mean arterial blood pressure and a decrease in heart rate. Plasma concentrations of atrial natriuretic peptide, renin activity, aldosterone, and guanosine 3',5'-cyclic monophosphate were not changed during the infusion of ADM. The current study demonstrates that ADM is present in renal glomerular and tubular cells and is a potent natriuretic peptide that may play an important role in the regulation of sodium excretion.
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PMID:Renal localization and actions of adrenomedullin: a natriuretic peptide. 773 22

Adrenomedullin (AM) is a potent vasodilatory peptide originally discovered in human pheochromocytoma tissue. AM and AM gene expression are widely distributed in the cardiovascular system, including the kidney. The co-localization of AM and its receptor components such as calcitonin receptor-like receptor (CRLR), receptor activity modifying protein (RAMP)2 and RAMP3 in the kidney, heart, and vasculature suggests an important role for the peptide as a regulator of renal, cardiac, and vascular function. Indeed, in addition to its cardiovascular effects, AM has renal vasodilatory, natriuretic, and diuretic actions. Consistent with these observations, immunohistochemical studies revealed that AM is stained in the collecting duct, distal convoluted tubules, vessels, and glomerular mesangial cells, endothelial cells and podocytes. Plasma AM levels are increased in patients with renal impairment in proportion to the severity of the disease. Previously we and other investigators showed that two molecular forms of AM, AM-glycine, an inactive form, and AM-mature, an active form, circulate in human plasma. Urine also contains both forms of AM; however, the AM-mature/AM-glycine ratio is higher in urine than in plasma. Interestingly, plasma AM-glycine and AM-mature levels are increased in renal failure, whereas urinary AM-glycine and AM-mature are decreased in this condition. These results indicate that the origin of urinary AM is different from that of plasma AM. Experimental studies showed that the renal tissue AM-mature/AM-glycine ratio is higher than that in plasma and urine. In addition, renal tissue concentrations of AM are increased in severely hypertensive rats. Considering that AM has antiapoptotic, antifibrotic, and antiproliferative effects, the increase of AM in renal disease may be a protective mechanism. In fact, AM gene delivery or long-term AM infusion significantly improved glomerular sclerosis, interstitial fibrosis, and renal arteriosclerosis in several malignant hypertensive models. This review describes the biochemistry, physiology, and circulating levels of AM and also discusses what is known about the pathophysiological role of AM in renal disease.
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PMID:Adrenomedullin in the kidney-renal physiological and pathophysiological roles. 1758 73