The molecular basis of secondary hyperparathyroidism in chronic renal failure.
Renal osteodystrophy is a debilitating complication of chronic renal failure and secondary hyperparathyroidism (2HPTH) is one of its central features. 2HPTH develops as a result of the low levels of serum calcium and 1,25-dihydroxyvitamin D [1,25(OH)2D3] and the high serum phosphate that occur in chronic renal failure. 1,25(OH)2D3 markedly decreases PTH gene transcription and its lack leads to 2HPTH. A low serum calcium increases PTH mRNA and iPTH levels while a high serum calcium has no effect on PTH gene expression. In experimental uremia there are increased levels of PTH mRNA. In chronic renal failure there is a shift in the calcium set-point to the right. This may be a function of a change in properties of the parathyroid cell calcium receptor, which is a G-protein coupled calcium sensor.
Rahamimov
R
R
Minerva Center for Calcium and Bone Metabolism, Hadassah University Hospital Jerusalem, Israel.
Silver
J
J
D002117:Calcitriol / Q000097:blood / Q000627:therapeutic use; D002118:Calcium / Q000097:blood / Q000627:therapeutic use; D002135:Calcium-Binding Proteins / Q000235:genetics; D012080:Chronic Kidney Disease-Mineral and Bone Disorder / Q000209:etiology*; D005786:Gene Expression Regulation / Q000235:genetics*; D006801:Humans; D006962:Hyperparathyroidism, Secondary / Q000097:blood* / Q000188:drug therapy / Q000209:etiology*; D007676:Kidney Failure, Chronic / Q000150:complications*; D010281:Parathyroid Hormone / Q000097:blood* / Q000235:genetics* / Q000378:metabolism; D010758:Phosphorus / Q000097:blood; D012333:RNA, Messenger / Q000235:genetics*; D014158:Transcription, Genetic / Q000235:genetics*
D002135:Calcium-Binding Proteins; D010281:Parathyroid Hormone; D012333:RNA, Messenger; D010758:Phosphorus; D002117:Calcitriol; D002118:Calcium