Fig. 10.

Indices of the CO₂ and NH₃ permeability of Aqp1a. A: indices of the Aqp1a-dependent CO₂ and NH₃ permeability (ΔpH_S*) and the Aqp1a-dependent (P_f*). The leftmost bar of CO₂ is an index of the Aqp1a-dependent CO₂ permeability. We subtracted the mean value of ΔpH_S induced by CO₂ in day-matched, H₂O-injected control oocytes (data contributing to the H₂O bar for Fig. 8A) from the ΔpH_S induced by CO₂ in individual oocytes expressing Aqp1a (data contributing to the Aqp1a bar for Fig. 8A). Similarly, the middle bar of NH₃ is an index of the Aqp1a-dependent NH₃ permeability, and the rightmost bar of P_f is the Aqp1a-dependent osmotic water permeability (P_f*). B: Aqp1a-dependent parameters normalized to P_f*. The leftmost hatched bar of Aqp1a is the result of dividing the Aqp1a-dependent index of CO₂ permeability of individual oocytes (data contributing to the bar for CO₂ in A) by the corresponding Aqp1a-dependent P_f values of the same oocytes (data contributing to the bar for P_f in A). The rightmost stippled bar is the result of a similar manipulation, but starting with the Aqp1a-dependent index of NH₃ permeability of individual oocytes (data contributing to the bar for NH₃ in A). The other three pairs of bars represent data reported in a previous study (30) on human AQP1, rat AQP4, and rat AQP5. C: ratio of Aqp1a-dependent indices of CO₂ and NH₃ permeability. The bar for Aqp1a is the result of dividing the Aqp1a-dependent index of CO₂ permeability of individual oocytes (data contributing to the bar for CO₂ in A) by the corresponding index of NH₃ permeability of the same oocytes (data contributing to the bar for NH₃ in A). The bars for human AQP1, rat AQP4, and rat AQP5 represent data reported in a previous study (30).