Effect of progesterone and its 17 alpha-hydroxyl derivative on human erythrocyte membrane

Effect of progesterone and 17 alpha-hydroxyprogesterone on human erythrocyte membrane was investigated by three methods. Prompt hemolysis test: Progesterone progressively reduced the membrane fragility at the concentration of 1.25 X 10(-5)-2.0 X 10(-4) M, but 17 alpha-hydroxyprogesterone had almost no effect. Continuous MCV analysis: When erythrocytes were transferred into 0.9 (w/v) % NaCl solution without progesterone after incubation with 0.5 M d-glucose for 2 hr at 37 degrees C, erythrocytes markedly expanded up to about 140 microns 3 and subsequently returned to nearly the original volume (about 95 microns 3) within 30-40 sec. Progesterone reduced the reversibility of expanded erythrocytes at the concentration of 1.25 X 10(-5)-1.0 X 10(-4) M. 17 alpha-Hydroxyprogesterone had little effect on the reversibility. Scanning electron microscopy: After incubation in isotonic buffered saline solution without progesterone for 12 hr at 37 degrees C, most of the erythrocytes were transformed from discocytes to echinocytes and sphero-echinocytes (echinocytes+sphero-echinocytes, greater than 80%). Progesterone (5.0 X 10(-5) and 1.0 X 10(-4) M) inhibited this transformation, so that a greater number of erythrocytes remained as discocytes than in the control. Moreover, at higher concentration of progesterone, stomatocytes emerged prominently (1.0 X 10(-4) M progesterone), followed by the increase in spherocytes (2.0 X 10(-4) M). 17 alpha-Hydroxyprogesterone, however, merely prevented the echinocytic progress from I to II or III at the concentration of 5.0 X 10(-5)-2.0 X 10(-4) M and slightly increased the number of discocytes at the higher concentration (2.0 X 10(-4) M).(ABSTRACT TRUNCATED AT 250 WORDS)