Regulation of red blood cell filterability by Ca2+ influx and cAMP-mediated signaling pathways

• Published in: American Journal of Physiology: Cell Physiology 1997-12, Vol.273 (6), p.C1828
• Main Authors: Oonishi, Tadahiro, Sakashita, Kanako, Uyesaka, Nobuhiro
• Format: Article
• Language: English
• ISSN: 0363-6143; 1522-1563
• DOI: 10.1152/ajpcell.1997.273.6.c1828

Nippon Telegraph and Telephone Corporation Medical Research Institute, Kanto Teishin Hospital, Tokyo 141; and Department of Physiology, Nippon Medical School, Tokyo 113, Japan To investigate the mechanism of the regulation of human red blood cell deformability, we examined the deformability under mechanical stress. Washed human red blood cells were rapidly injected through a fine needle, and their filterability was measured using a nickel mesh filter. The decrease in filterability showed a V-shaped curve depending on the extracellular Ca 2+ concentration; the maximum decrease was achieved at ~50 µM. The decreased filterability was accompanied by no change in cell morphology and cell volume, indicating that the decrease in filterability can be ascribed to alterations of the membrane properties. Ca 2+ entry blockers (nifedipine and felodipine) inhibited the impairment of filterability under mechanical stress. Prostaglandins E 1 and E 2 , epinephrine, and pentoxifylline, which are thought to modulate the intracellular adenosine 3',5'-cyclic monophosphate (cAMP) level of red blood cells, improved or worsened the impaired filterability according to their expected actions on the cAMP level of the cells. These results strongly suggest that the membrane properties regulating red blood cell deformability are affected by the signal transduction system, including Ca 2+ -dependent and cAMP-mediated signaling pathways. calcium entry blockers, prostaglandins, epinephrine, pentoxifylline; adenosine 3',5'-cyclic monophosphate; calcium ion