The formation of heteroagglutinins in rats "chemically" splenectomized by ethyl palmitate, in comparison to animals surgically splenectomized.

In Wistar rats "chemically splenectomized" by an i.v. injection of ethyl palmitate the formation of heteroagglutinins against human O-erythrocytes has been followed. Ethyl palmitate applied 2 hrs before immunization induced on the 5th day a significant decrease of the antibody level. This temporary inhibition, however, was at a later stage replaced by a significant increase of antibody level with the peak of 8--14 days. Animals surgically splenectomized 24 hrs prior to immunization displayed a weak antibody response throughout the experiment. An injection of the ethyl palmitate on the 6th day after immunization induced a pronounced and persistent decrease of the antibody level. Surgical splenectomy performed within the same interval had a comparable effect. The experiments revealed that the inhibitory effect of ethyl palmitate on antibody production was temporary only, and at a later stage could be compensated by an enhanced antibody activity.