Abstract
IN typical physiological solutions, CO2 is in equilibrium with HCO3− and H+ (CO2 + H2O⇆HCO3− + H+). Because one cannot independently alter CO2 and HCO3− concentrations and pH, it is impossible to distinguish between the effects of CO2 and HCO3−on physiological processes. Here we describe a continuous-flow, rapid-mixing approach for generating out-of-equilibrium CO2/ HCO3− solutions with a physiological pH and CO2 (but little HCO3−), or pH and HCO3− (but little CO2). We have exploited these out-of-equilibrium solutions to introduce HCO3− exclusively to either the outside or inside of a squid giant axon, and verify the presence of a new K/HCO3 cotransporter. The out-of-equilibrium approach could be useful in a variety of applications for independently controlling CO2 and HCO3− concentrations and pH.
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References
Brinley, F. J. Jr & Mullins, L. J. J. gen. Physiol. 50, 2303–2311 (1967).
Hinke, J. A. M. in Glass Electrodes for Hydrogen and Other Cations: Principle and Practice (ed. Eisenman, G.) 464–477 (Dekker, New York, 1967).
Boron, W. F. & De Weer, P. J. gen. Physiol. 67, 91–112 (1976).
Cabantchik, Z. I., Knauf, P. A. & Rothstein, A. Biochim. biophys. Acta 515, 239–302 (1978).
Thomas, R. C. Nature 262, 54–55 (1976).
Boron, W. F. & Boulpaep, E. L. J. gen. Physiol. 81, 53–94 (1983).
Frankenhauser, B. & Hodgkin, A. L. J. Physiol. 131, 341–376 (1956).
Roos, A. & Boron, W. F. Physiol. Rev. 61, 296–434 (1981).
Aickin, C. C. J. Physiol. 479, 301–316 (1994).
Baro, I., Eisner, D. A., Raimback, S. J. & Wray, S. J. Physiol. 417, 161P (1989).
Pocock, G. & Richards, C. D. Eur. J. Neurosci. 4, 136–143 (1992).
Roughton, F. J. W. J. Am. chem. Soc. 63, 29–30 (1941).
Rossi-Bernardi, L. & Berger, R. L. J. biol. Chem. 243, 1297–1302 (1968).
Dalziel, K. Biochem. J. 55, 79–90 (1953).
Nattie, E. E. in Regulation of Breathing, Lung Biology in Health and Disease Vol. 79 (eds Dempsey, J. A. & Pack, A. I.) 473–510 (Dekker, New York, 1995).
Dorman, P. J., Sullivan, W. J. & Pitts, R. F. J. clin. Invest. 33, 82–90 (1954).
Brazeau, P. & Gilman, A. Am. J. Physiol. 175, 33–38 (1953).
Ho, C. & Sturtevant, J. M. J. biol. Chem. 238, 3499–3501 (1963).
Gibbons, B. H. & Edsall, J. T. J. biol. Chem. 238, 3502–3507 (1963).
Eigen, M., Kustin, K. & Maass, G. Z. Physik. Chem. 30, 130–136 (1961).
Boron, W. F. & Russell, J. M. J. gen. Physiol. 81, 373–399 (1983).
Hogan, E. M., Cohen, M. A. & Boran, W. J. gen. Physiol. (in the press).
Hogan, E. M., Cohen, M. A. & Boran, W. J. gen. Physiol. (in the press).
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Zhao, J., Hogan, E., Bevensee, M. et al. Out-of-equilibrium CO2/HCO3− solutions and their use in characterizing a new K/HCO3 cotransporter. Nature 374, 636–639 (1995). https://doi.org/10.1038/374636a0
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DOI: https://doi.org/10.1038/374636a0
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