抄録
In present paper, isoenzyme anomalies of lactate dehydrogenase in two cases are reported.
One case is a healthy young man and the other case is a 53 aged male patient carrying rectal cancer.
Biochemical and immunological investigations for both LDH-anomalies were performed and different properties have been found, respectively.
Case 1;
LDH-anomalies on electrophoretic pattern were to show nondetectable LDH2, broad LDH3, and specified abnormal fraction between LDH3and LDH4.
These anomalies of this case have been originated from the cause of binding of LDH subunit to IgA-κ type. This binding was more specific to LDH2, but had not species specificity.
Case 2;
This main anomaly showed abnormal extra-band between LDH3and LDH4. This band was stable in heat (56°C, 30 min) or in 2 M urea, and had high molecular properties, but could not be prove binding to ordinary serum proteins.
This abnormal high molecular LDH isoenzyme had shifted to normal molecular size by action under stronger ionic strength. Electrophoretic mobility of dissociated LDH isoenzyme, however, was as same as originated high molecular one.
LDH isoenzyme patterns in red blood cells and urine from the patient were almost normal.
It was very interesting that this abnormal pattern was disappeared at 71 days after its the first noticed.
As above results, the authors speculate that this abnormal LDH isoenzyme consists of a few subunits with ionic bond and its binding is transient.
