The maintenance of blood colloid: passage of stored gum acacia from the cells to the circulation after plasmapheresis.

Removal of blood plasma by plasmapheresis from dogs made hypoproteinemic by injections of gum acacia over long periods of time, has resulted in the removal of more gum acacia than was originally present in the plasma. Gum acacia injections had been discontinued previous to the start of the experiments, and hence it must be concluded that the excess amounts of acacia were derived from deposits in the various organs. These observations verify the previous suggestion that the increase in blood acacia in the hypoproteinemic dog on a low protein diet is due to the transfer of acacia to the blood from its sites of deposit in the body. The experiments further suggest that the colloid content of the blood stream is maintained at the expense of tissue colloids, and support the idea that colloidal substances may pass in and out of cells.