High-performance liquid chromatographic characterization of neurophysins in chronic renal failure

Levels of immunoreactive (IR) oxytocin (OT)-associated or estrogen-stimulated neurophysin (ESN) and vasopressin-associated or nicotine-stimulated neurophysin (NSN) were measured in plasma of patients with chronic renal failure before and after hemodialysis (HD) and intermittent peritoneal dialysis (IPD), and during continuous ambulatory peritoneal dialysis (CAPD). ESN-IR in 17 patients before HD was 24.4 +/- 2.7 ng/ml (mean +/- SEM) and increased after HD to 33.2 +/- 4.1 ng/ml (P less than 0.001). ESN-IR in 17 patients with CAPD was 15.2 +/- 3.4 ng/ml, significantly lower than in patients undergoing HD, P less than 0.001. In patients receiving IPD (n = 6), ESN was 11.6 +/- 3.7 ng/ml and did not change significantly after IPD. Levels of ESN in patients with renal failure were increased compared with levels in normal individuals, 1.0 +/- 0.1 ng/ml. Levels of ESN were not correlated with laboratory parameters that may be abnormal in renal failure. NSN levels in 16 of 17 patients undergoing HD were 3.2 +/- 0.34 ng/ml and in 14 of 17 patients with CAPD were 2.9 +/- 0.4 ng/ml, respectively. ESN before HD (r = 0.63, P less than 0.01), after HD (r = 0.85, P less than 0.001), and in patients with CAPD (r = 0.83, P less than 0.001) and IPD (r = 0.81, P less than 0.05) correlated significantly with an OT-like peptide previously found to be increased in renal failure.(ABSTRACT TRUNCATED AT 250 WORDS)