Circadian Secretion Pattern of Copeptin, the C-Terminal Vasopressin Precursor Fragment

Copeptin, the C-terminal peptide of provasopressin, is stoichiometrically released with arginine vasopressin (AVP). In contrast to AVP, it is stable ex vivo (1) and reflects the AVP system, as shown in diabetes insipidus or the syndrome of inappropriate antidiuretic hormone secretion(2). Copeptin is a reliable marker of severe stress, with increased concentrations found in cases of critical illness, sepsis, hemorrhagic shock, and stroke(2). The serum copeptin concentration is profoundly and immediately stimulated after myocardial infarction(3). The absence of such stimulation within the first hours after the onset of symptoms has recently been proposed as an important negative predictor for excluding the likelihood of infarction in patients with unspecific chest pain(3). Any further use of the peptide as a marker critically depends on clear cutoffs between health and disease. To better characterize the diagnostic accuracy of …