title: Diagnostic value of serum creatine kinase and lactate dehydrogenase isoenzyme determinations for monitoring early cardiac damage in rats.
abstract: Serum activities of creatine kinase (CK, EC 2.7.3.2) and CK isoenzymes, lactate dehydrogenase (LDH, EC 1.1.1.27) and LDH isoenzymes, alpha-hydroxybutyrate dehydrogenase (alpha-HBDH, no EC) and the LDH/alpha-HBDH ratio were studied following a single s.c. application of 5-250 mg isoproterenol/kg body weight (b.w.) in rats. Measurements of the serum enzymes and histological and enzyme-histochemical examinations of hearts were performed 2, 4, 6, 8 and 24 h after treatment. A drastic increase in serum levels of the isoenzymes CK-MB, LDH1, LDH2 and alpha-HBDH and decrease in the ratio LDH/alpha-HBDH were observed from 2 h onwards after isoproterenol application in all dose groups, the maximum effect being after 4-8 h. Focal cellular injury in the myocardium could also be observed from 2 h onwards after isoproterenol application by an enzyme-histochemical method using nitro blue tetrazolium (NBT) whereas the earliest histological alterations using haematoxylin and eosin (HE) stain could be detected 6 h after treatment. A dose-dependent effect as to enzyme values as well as to myocardial necrosis was observed 24 h after isoproterenol application. No kidney damage could be detected on the basis of serum urea nitrogen and histological examinations. Thus, measurement of serum activities of CK-MB isoenzyme alone or LDH1-2 isoenzymes in combination with other tests to exclude kidney damage are valuable indicators of cardiac lesions in rats.
authors.affiliation: Experimental Toxicology, Research Laboratories Schering, Berlin, F.R.G.
authors.forename: M
authors.initials: M
authors.lastname: Preus
authors.forename: A S
authors.initials: AS
authors.lastname: Bhargava
authors.forename: A E
authors.initials: AE
authors.lastname: Khater
authors.forename: P
authors.initials: P
authors.lastname: Günzel
mesh_terms: D000818:Animals; D003402:Creatine Kinase / Q000097:blood*; D004305:Dose-Response Relationship, Drug; D006321:Heart / Q000187:drug effects*; D006651:Histocytochemistry; D007527:Isoenzymes; D007545:Isoproterenol / Q000633:toxicity*; D007770:L-Lactate Dehydrogenase / Q000097:blood*; D008297:Male; D008991:Monitoring, Physiologic; D009206:Myocardium / Q000201:enzymology; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D007527:Isoenzymes; D007770:L-Lactate Dehydrogenase; D003402:Creatine Kinase; D007545:Isoproterenol