title: Immunoreactive parathyroid hormones in the circulation and cerebrospinal fluid from patients with renal failure: possible restriction of parathyroid hormone by the blood-brain barrier.
abstract: Parathyroid hormone is reported to be a possible causal factor of abnormalities of electroencephalograms of patients with renal failure. In this study, the parathyroid hormone levels were compared in the circulation and cerebrospinal fluid of seven normal subjects and 22 patients with renal failure including those who showed abnormal electroencephalograms. The circulating levels of both C-terminal and N-terminal parathyroid hormone in the subjects studied showed a positive correlation (C-terminal, r = 0.58, P less than 0.01; N-terminal, r = 0.61, P less than 0.01) with the grade of abnormality of the electroencephalogram. However, the levels of C-terminal and N-terminal parathyroid hormone in the cerebrospinal fluid of both normal subjects and patients with renal failure were below the detectable limit (C-terminal, less than 0.1 ng/ml; N-terminal, less than 2.3 pg/ml). These data suggest that in patients with renal failure, the effect of parathyroid hormone on the central nervous system is mediated in some other way than via the cerebrospinal fluid.
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001806:Blood Urea Nitrogen; D001812:Blood-Brain Barrier; D002118:Calcium / Q000097:blood; D003404:Creatinine / Q000097:blood / Q000134:cerebrospinal fluid; D004569:Electroencephalography; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood / Q000134:cerebrospinal fluid / Q000378:metabolism*; D010710:Phosphates / Q000097:blood; D011188:Potassium / Q000097:blood; D012016:Reference Values; D014508:Urea / Q000134:cerebrospinal fluid
chemical_list: D010281:Parathyroid Hormone; D010710:Phosphates; D014508:Urea; D003404:Creatinine; D011188:Potassium; D002118:Calcium