Abstract
It is well known that following partial removal of an endocrine gland the remaining parts of the organ tend to compensate for the loss by undergoing active hypertrophy and hyperplasia. This phenomenon has been referred to descriptively as compensatory hypertrophy. The isolation of purified hormone principles made it possible to study the effect of hormone overdosage on endocrine glands, and it soon became evident that in most cases excessive treatment with a certain glandular substance resulted in the eventual atrophy of the cells which normally have the task of producing this glandular product. It is not within the scope of this communication to review the extensive relevant literature. Suffice it to mention that the thyroid gland undergoes involution under the influence of an overdose of a thyroid preparation,1 the pancreatic islets, especially the insulin producing beta cells, involute following treatment with insulin,2 the ovaries after administration of