Changes in plasma copeptin, the c-terminal portion of arginine vasopressin during water deprivation and excess in healthy subjects.

CONTEXT The measurement of arginine vasopressin (AVP) is often cumbersome because it is unstable with a short half-life time. AVP is derived from a larger precursor peptide along with the more stable peptide copeptin. Copeptin is the C-terminal part of provasopressin and has been shown to be a useful tool to indicate AVP concentration in critically ill patients. OBJECTIVE The objective of the study was to evaluate the clinical usefulness of copeptin as a new marker in disordered states of blood volume and plasma osmolality. DESIGN AND SETTING This was a prospective observational study in a university hospital. PARTICIPANTS AND MAIN OUTCOME MEASURES Three techniques with respective control studies were used in 24 healthy adults to produce changes in plasma osmolality and/or volume: 1) a 28-h water deprivation, 2) a 17-h hypertonic saline infusion combined with thirsting, and 3) a hypotonic saline infusion with iv desmopressin administration during free water intake. RESULTS Water deprivation produced a weight loss of 1.7 kg, an increase in plasma osmolality to 294.8 +/- 4.3 mosmol/kg, and an increase of copeptin from 4.6 +/- 1.7 pmol/liter to 9.2 +/- 5.2 pmol/liter (P < 0.0001). During hypertonic saline infusion and thirsting with a raise of plasma osmolality to 296.1 +/- 3.4 mosmol/kg, copeptin increased from 4.9 +/- 3.0 pmol/liter to 19.9 +/- 4.8 pmol/liter (P < 0.0001). Conversely, during hypotonic saline infusion, plasma osmolality decreased to 271.3 +/- 4.1 mosmol/kg, and copeptin decreased from 6.2 +/- 2.4 pmol/liter to 2.4 +/- 2.1 pmol/liter (P < 0.01). CONCLUSION Copeptin shows identical changes during disordered water states as previously shown for AVP. It might be a reliable marker of AVP secretion and substitute for the measurement of circulating AVP levels in clinical routine.

[1]  A. G. Semenov,et al.  The brain natriuretic peptide (BNP) precursor is the major immunoreactive form of BNP in patients with heart failure. , 2007, Clinical chemistry.

[2]  N. Morgenthaler,et al.  Copeptin and arginine vasopressin concentrations in critically ill patients. , 2006, The Journal of clinical endocrinology and metabolism.

[3]  N. Morgenthaler,et al.  Course of Vasopressin and Copeptin Plasma Concentrations in a Patient with Severe Septic Shock , 2006, Anaesthesia and intensive care.

[4]  J. Struck,et al.  Immunoluminometric assay for measurement of the C-terminal endothelin-1 precursor fragment in human plasma. , 2006, Clinical chemistry.

[5]  J. Struck,et al.  Assay for the measurement of copeptin, a stable peptide derived from the precursor of vasopressin. , 2006, Clinical chemistry.

[6]  J. Struck,et al.  Copeptin, a stable peptide derived from the vasopressin precursor, is elevated in serum of sepsis patients , 2005, Peptides.

[7]  M. Gheorghiade,et al.  Vasopressin antagonism in heart failure. , 2005, Journal of the American College of Cardiology.

[8]  J. Struck,et al.  Measurement of midregional proadrenomedullin in plasma with an immunoluminometric assay. , 2005, Clinical chemistry.

[9]  Gabor Szinnai,et al.  Effect of water deprivation on cognitive-motor performance in healthy men and women. , 2005, American journal of physiology. Regulatory, integrative and comparative physiology.

[10]  V. Wenzel,et al.  Vasopressin during cardiopulmonary resuscitation: A progress report , 2004, Critical care medicine.

[11]  E. Breslow,et al.  Properties of human vasopressin precursor constructs: inefficient monomer folding in the absence of copeptin as a potential contributor to diabetes insipidus. , 2004, Biochemistry.

[12]  P. Factor,et al.  Role of vasopressin in the management of septic shock , 2004, Intensive Care Medicine.

[13]  J. Struck,et al.  Immunoluminometric assay for the midregion of pro-atrial natriuretic peptide in human plasma. , 2004, Clinical chemistry.

[14]  H. Ruskoaho Cardiac hormones as diagnostic tools in heart failure. , 2003, Endocrine reviews.

[15]  G. S. Ranger,et al.  THE PHYSIOLOGY AND EMERGING ROLES OF ANTIDIURETIC HORMONE , 2002, International Journal of Clinical Practice.

[16]  D. Keefe,et al.  Selected Contribution: Sex differences in osmotic regulation of AVP and renal sodium handling , 2001 .

[17]  G. Robertson Antidiuretic hormone. Normal and disordered function. , 2001, Endocrinology and metabolism clinics of North America.

[18]  W. Abraham,et al.  Hormones and hemodynamics in heart failure. , 1999, The New England journal of medicine.

[19]  D. Häussinger,et al.  Effects of hyper- and hypoosmolality on whole body protein and glucose kinetics in humans. , 1999, American journal of physiology. Endocrinology and metabolism.

[20]  F. Waldhauser,et al.  Improved extraction procedure and RIA for determination of arginine8-vasopressin in plasma: role of premeasurement sample treatment and reference values in children. , 1999, Clinical chemistry.

[21]  Robertson Gl The use of vasopressin assays in physiology and pathophysiology. , 1994 .

[22]  W. Abraham,et al.  Vasopressin in pathophysiological states. , 1994, Seminars in nephrology.

[23]  M. Georgieff,et al.  Stress hormone response during and after cardiopulmonary resuscitation. , 1992, Anesthesiology.

[24]  R. Cody,et al.  Plasma and Platelet Vasopressin in Essential Hypertension and Congestive Heart Failure , 1983, Hypertension.

[25]  G. Schütz,et al.  Nucleotide sequence of cloned cDNA encoding bovine arginine vasopressin–neurophysin II precursor , 1982, Nature.

[26]  S. Athar,et al.  The interaction of blood osmolality and blood volume in regulating plasma vasopressin in man. , 1976, The Journal of clinical endocrinology and metabolism.

[27]  T. Brennan,et al.  The role of blood osmolality and volume in regulating vasopressin secretion in the rat. , 1973, The Journal of clinical investigation.

[28]  G. Robertson,et al.  Development and clinical application of a new method for the radioimmunoassay of arginine vasopressin in human plasma. , 1973, The Journal of clinical investigation.

[29]  D. A. Holwerda A glycopeptide from the posterior lobe of pig pituitaries. 2. Primary structure. , 1972, European journal of biochemistry.