1977 年 97 巻 9 号 p. 1017-1021
Penicillin G added to a human erythrocyte suspension was found to exert the following actions on their plasma membranes : (1) It inhibits acetylcholinesterase activity in concentrations higher than 100 mM and this inhibitory effect increases with time. The lost activity is not restored by washing of the treated cells. (2) Penicillin G added to a hypotonic hemolyzing medium in a concentration over 5 mM increases osmotic resistance of the cells. (3) It promptly induces, in a similar concentration as in (2), the membrane externalization and the resulting echinocyte-spherocyte formation. Upon continuing the incubation, however, these cells change their shape further, showing pictures of a combined type of the membrane externalization and internalization. When these cells are washed with saline, they show a typical picture of the membrane internalization. Penicillin G in the surrounding medium was rapidly taken up by the cells into the intracellular fluid and, therefore, it is possible that it may act on the membrane from both the outer and inner surfaces.