title: Circadian rhythms of serum concentrations of 12 enzymes of clinical interest.
abstract: A total of 25 apparently healthy adults (13 men and 12 women), 29.5 years (SD = 3.6 years) of age, served as subjects in a 24-h study conducted in Barcelona, Spain, in the spring of 1990. The group had a homogeneous pattern of meals, activity, and behavior. Six blood samples were collected at 4-h intervals over a single 24-h period beginning at 10:00 h. The oral temperature was measured at 2-h intervals to facilitate an independent biological time reference for the local population being studied. The serum concentration of 12 enzymes of clinical interest were measured in each sample: creatine kinase, creatine kinase 2, alanine aminotransferase, aspartate aminotransferase, gamma-glutamyltransferase, alkaline phosphatase, cholinesterase, lactate dehydrogenase, lactate dehydrogenase 1, 5'-nucleotidase, pancreatic alpha-amylase, and triacylglycerol lipase. We supposed that all experimental data obtained for a quantity came from a single "hypothetical subject" that represented the central tendency of the population and then these data were analyzed for circadian rhythm by single cosinor. A statistically significant circadian rhythm was detected in all quantities studied (p < or = 0.05) except for serum concentrations of pancreatic alpha-amylase and triacylglycerol lipase. The maximum daily rhythmic variation was approximately 10% (interval, 6-14%) for all quantities studied except pancreatic alpha-amylase (2.6%). This rhythmic variation is greater than the analytical variation except for 5'-nucleotidase and pancreatic alpha-amylase. The acrophases for the quantities studied (except that of triacylglycerol lipase) coincide with times near those of the oral temperature acrophase (18:01 local time). The results of this study will doubtless contribute to further documentation of the structure of the human circadian timing system and to establishment of time-qualified reference intervals for a defined group of subjects.
authors.affiliation: Servei de Bioquímica Clínica, Hospital Prínceps d'Espanya, L'Hospitalet de Llobregat, Barcelona.
authors.forename: A
authors.initials: A
authors.lastname: Rivera-Coll
authors.forename: X
authors.initials: X
authors.lastname: Fuentes-Arderiu
authors.forename: A
authors.initials: A
authors.lastname: Díez-Noguera
mesh_terms: D015720:5'-Nucleotidase / Q000097:blood; D000328:Adult; D000410:Alanine Transaminase / Q000097:blood; D000469:Alkaline Phosphatase / Q000097:blood; D001219:Aspartate Aminotransferases / Q000097:blood; D002802:Cholinesterases / Q000097:blood; D002940:Circadian Rhythm; D004796:Clinical Enzyme Tests / Q000379:methods; D003402:Creatine Kinase / Q000097:blood; D004798:Enzymes / Q000097:blood*; D005260:Female; D006801:Humans; D007527:Isoenzymes; D007770:L-Lactate Dehydrogenase / Q000097:blood; D008049:Lipase / Q000097:blood; D008297:Male; D000516:alpha-Amylases / Q000097:blood; D005723:gamma-Glutamyltransferase / Q000097:blood
chemical_list: D004798:Enzymes; D007527:Isoenzymes; D007770:L-Lactate Dehydrogenase; D005723:gamma-Glutamyltransferase; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase; D003402:Creatine Kinase; D008049:Lipase; D002802:Cholinesterases; D000469:Alkaline Phosphatase; D015720:5'-Nucleotidase; D000516:alpha-Amylases