Beschreibung:
The isoenzymes of lactate dehydrogenase (E. C. 1. 1. 1. 27.) from the periodontal ligament on the root surface of extracted erupted permanent human teeth have been separated and quantitated by means of cellulose acetate membrane electrophoresis.LDH‐3 and LDH‐4 were the predominating isoenzymes. and smaller amounts of LDH‐2 and LDH‐5 were also present. Only traces of LDH‐1 could be seen. The results indicate the presence of both aerobic and anaerobic metabolic pathways in the human periodontal ligament.These pathways bring about an efficient, economical energy production under normal circumstances, and make the survival of this tissue possible under hypoxic conditions, when the blood supply is briefly interrupted. The results further show that determinations of the survival time of the periodontal ligament on a tooth outside its alveolus have to be made by activity measurements of both aerobic and anaerobic enzymes.