Levels of the oxytocin-associated and vasopressin-associated neurophysins in plasma and their responses in essential hypertension.
A group of 89 individuals with essential hypertension was evaluated with several measurements including the neurophysin believed to be the human oxytocin neurophysin (OT-Np), and the human vasopressin neurophysin (VP-Np). The neurophysins are proteins synthesized within cells of the supraoptic and paraventricular nuclei in conjunction with their respective hormones oxytocin and vasopressin as part of a common precursor molecule and so may reflect the simultaneous presence in plasma of their associated hormones. A poor but statistically significant correlation was noted between levels of OT-Np and renin activity in plasma (PRA) either supine (r = 0.248) or erect (r = 0.255). Levels of OT-Np averaged 1.75 ng/ml and were inversely correlated with creatinine (r = -0.252), supine blood pressure (r = -0.450), plasma volume (r = -0.327), and 24-hour urine sodium (r = -0.313). Levels of Ot-Np could be suppressed by infusion of physiologic saline. Levels of OT-Np were lower in the volume expanded state and were positively correlated with the quantity of sodium excreted into a 24-hour urine collected after the infusion (r = 0.426) and inversely correlated with the supine systolic (r = -0.379) and supine diastolic (r = -0.455) blood pressures recorded after the infusion of saline. Oestrogen, a stimulus to the secretion of OT-Np, did not account for the elevation of OT-Np observed in the study, since mean levels of oestradiol (E2) in a subset of the patients with elevated OT-Np (E2 = 36 pg/ml) were not different from levels in subjects with lower values of OT-Np (E2 = 45 pg/ml).(ABSTRACT TRUNCATED AT 250 WORDS)
D000328:Adult; D000367:Age Factors; D001794:Blood Pressure; D003404:Creatinine / Q000097:blood; D004298:Dopamine / Q000652:urine; D004958:Estradiol / Q000097:blood; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood* / Q000652:urine; D008297:Male; D008875:Middle Aged; D009481:Neurophysins / Q000097:blood*; D010121:Oxytocin; D010953:Plasma Volume; D011187:Posture; D012083:Renin / Q000097:blood; D012964:Sodium / Q000652:urine; D014667:Vasopressins
D009481:Neurophysins; D014667:Vasopressins; D004958:Estradiol; D010121:Oxytocin; D012964:Sodium; D003404:Creatinine; D012083:Renin; D004298:Dopamine