EFFECTS OF ADRENOCORTICOTROPHIC HORMONE ON THE PHOSPHORUS METABOLISM OF LYMPHOID TISSUE*

Abstract

The subcutaneous injection of a single dose of adrenocorticotrophic hormone (ACTH) in mice of the CBA strain produced a series of histological changes in lymphoid tissues characterized by three phases: degenerative, repair, and recovery (Dougherty and White, 1945). The degenerative phase was apparent in one hour and persisted for a six hour period. This phase was characterized by pycnosis of medium sized and small lymphocytes, shedding of cytoplasm of lymphocytes, decreased number of lymphocytes, marked edema, and cessation of mitosis. The repair phase which began at six hours following hormone injection included phagocytosis of nuclear debris and deposition of basophilic material in the cytoplasm of reticular cells. The recovery changes started at approximately nine hours after ACTH administration and were characterized by mitoses in the remaining lymphocytes of lymphoid tissue, maturation of reticular lymphocytes and differentiation of reticular lymphocytes from reticular cells. Within 24 hours after ACTH injection the lymphoid tissue resembled that of normal animals except for the thymus,