THE RELATIONSHIP BETWEEN TISSUE CHLORIDE AND PLASMA CHLORIDE

Abstract

Most of the chloride of the cat''s body is diffusible. It may be removed by long perfusion with Ringer-Locke soln. made up with the sulfates of Na, Ca, and K instead of the chlorides. To this soln. are added chloride-free beef cells and gum acacia. By this technic plasma chloride has been reduced to as low as 6% of normal. In certain tissues, such as the red cells, skeletal muscle, the liver and the kidney all of the chloride is diffusible and tissue chloride varies directly with plasma chloride. In other tissues such as stomach, spleen and salivary glands there is evidence for an indiffusible chloride fraction which is not removed by perfusion. in addition to a diffusible fraction which varies directly with plasma chloride. This retention of chloride is particularly striking in central nervous tissue. Cerebrum, cerebellum and spinal cord all hold their chloride tenaciously, and lose very little even when plasma chloride has been greatly reduced. At the same time, peripheral nerve loses most of its chloride. The theory which holds that chloride is able to penetrate only into extracellular water must not be extended uncritically from muscle to all other tissues. The data suggest very strongly that in some of the tissues a considerable fraction of chloride is intracellular. Except in the erythrocyte, the sulfate ion probably cannot penetrate the living cell membranes. It cannot, therefore, exchange with intracellular chloride, whose presence is thus made manifest in all tissues where it occurs.