This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous (Enzymes), Subject name: Biochemistry
Enzymes found in CSF: 
Select and explain. 
A. GGT + ALP, B. ALP + CK-MB, C. CK + LDH, D. Deaminase and Peroxidase
C: CK + LDH
Answer: C: CK + LDH 
Explanation: Ans. c. CK + LDH (Ref: Textbook of Medical Biochemistry by Dinesh Puri 2/e p154, 155)CK (Subunit composition BB) and LDH-3 (Subunit composition HHMM) are found in brain (CSF).Tissue Distribution of Lactate Dehydrogenase IsoenzymeIsoenzymeSubunit compositionTissuePercentage in serumLDH-1HHHHMyocardium, RBCQ30LDH-2HHHMMyocardium, RBCQ35LDH-3HHMMBrainQ, kidney20LDH-4HMMMSkeletal muscle, liverQ10LDH-5MMMMSkeletal muscle, liverQ5 Characteristics of CK IsoenzymesIsoenzymeSubunit compositionTissuePercentage in serumCKBBBrainQ30CKMBHeartQ35CKMMSkeletal muscleQ20