Membrane pores in hypotonically dialyzed sheep erythrocytes remain open after three weeks of storage: entrapment of different stokes radius probes, [14C]sucrose and [3H]inulin.

Sheep carrier erythrocytes were prepared from dialyzed cells stored for 3 weeks. The initial pore size in freshly dialyzed cells exceeds the Stokes radius of that for hemoglobin. Hypotonically dialyzed erythrocytes are then very stable in a porous state. Two probes of different Stokes radius were used to determine the relative size of the pores. Sheep erythrocytes entrap inulin to a greater extent than sucrose, a much smaller molecule. With storage, a greater fraction of dialyzed cells become impermeable to inulin than to sucrose indicative of pore size greater than 5.2 less than 20 A. Since hemoglobin content did not change relative to storage, the pore size was less than the Stokes radius of hemoglobin. Pores generated by controlled hypotonic dialysis are unlike the single rupture pore found in erythrocyte ghosts.