| Popis: |
Chloride/bicarbonate exchange is nearly ubiquitous among vertebrate cells (Alper, 1991). In erythrocytes, it serves to increase the CO2carrying capacity of the blood so as to increase delivery to the lungs for expiration of the CO2produced by cellular respiration (Tanner, 1993). In other cells, chloride/bicarbonate exchange participates in the maintenance of intracellular pH, volume, and chloride concentration. Chloride/bicarbonate exchange acid- loads cells in response to intracellular alkalinization, or participates with sodium/proton exchange in regulatory volume increase. Polarized epithelial cells restrict some of their chloride/bicarbonate exchange functions to apical or basolateral membranes in order to mediate vectorial transepithelial transport of bicarbonate and/or chloride. The only chloride/bicarbonate exchangers of known identity are the AE gene products. |
