title: Protein Z in healthy human individuals and in patients with a bleeding tendency.
abstract: Protein Z is a vitamin-K-dependent plasma glycoprotein; its physiological function is not clear. Low protein Z levels were found in patients with otherwise unexplained bleeding disorders. It was therefore suggested that low protein Z levels might be associated with a bleeding diathesis. In the present study we measured protein Z levels in plasma samples of 48 patients with a suspected bleeding disorder and in plasma samples of 200 healthy adult individuals. We found protein Z to have a wide normal range in healthy men and women. Significantly lower protein Z levels were observed in women compared to men, whereas no correlation was found with age or other vitamin-K-dependent coagulation proteins. None of the 48 patients with a bleeding disorder had a protein Z level below the normal range. However, protein Z was significantly lower in the group of male patients with a bleeding history as compared to healthy men. In conclusion, our data indicate that low-normal protein Z levels are not associated with a bleeding tendency. However, it remains to be determined whether a low protein Z level is a weak cofactor associated with an increased bleeding tendency and whether decreased or absent protein Z (conditions not detected in our patients) might constitute a haemorrhagic diathesis.
authors.affiliation: Central Haematology Laboratory, University of Bern, Inselspital, Switzerland.
authors.forename: S
authors.initials: S
authors.lastname: Ravi
authors.forename: T
authors.initials: T
authors.lastname: Mauron
authors.forename: B
authors.initials: B
authors.lastname: Lämmle
authors.forename: W A
authors.initials: WA
authors.lastname: Wuillemin
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001798:Blood Proteins; D002648:Child; D005260:Female; D006474:Hemorrhagic Disorders / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012016:Reference Values
chemical_list: D001798:Blood Proteins; C026080:plasma protein Z