Table 1.
Permeabilities and carbonic anhydrase (CA) activities of isolated epithelial cells from the proximal and distal colon of the guinea pig
| PCO2 | PHCO3 | Ain | Aex | Atot | n | |
|---|---|---|---|---|---|---|
| Proximal | 17 × 10−3 | 10 × 10−4 | 41 000 | 2.5 | 10 | 23 |
| colonocytes | ±9 × 10−3 | ±6 × 10−4 | ±16 000 | ±0.5 | ±3 | |
| Distal | 1.0 × 10−3 | 0.62 × 10−4 | 900 | 1.5 | 2.5 | 14 |
| colonocytes | ±0.9 × 10−3 | ±0.40 × 10−4 | ±630 | ±0.2 | ±0.8 |
PCO2 and PHCO3 are permeabilities of CO2 and HCO3− measured in centimetres per second. Given are means ±s.d.Atot is the total CA activity of isolated colonocytes, intra- plus extracellular CA. Ain is intracellular, Aex is extracellular CA activity. n is the number of mass spectrometric determinations. Temperature was 20°C.