[Human plasma lactic dehydrogenase activity: individual variations and reference intervals].

Out of a population of 8 7600 people of all origins, we drew up frequent values for the activity of total lactate dehydrogenase. From these values, we defined a reference interval on a selected population. Variations between individuals were determined in relation to the following factors: age (8 to 70 years), sex, height, weight, socio-prefessional categories, any excess weight, exercise and drugs. There exist definite variations in relation to age, especially in children. On the other hand, this enzyme shows little variation in relation to the morphology of the individual adult. Socio-professional groups have more influence on the activity of total lactate dehydrogenase.