Net mean uptake rates of Na+ and Cl− across the intestinal epithelium in eight marine teleost fish
| Species . | Net Cl− flux . | Net Na+ flux . | ΔNa+-Cl− . | Net HCO3− flux . | % of Cl− flux . |
|---|---|---|---|---|---|
| Parophrys vetulus1,§ | 0.4 | 0.2 | −0.2 | −0.2 | 50 |
| Citharichthys dordidus2,* | 3.5 | 2.3 | −0.9 | −0.9 | 26 |
| Platichthys flesus3,* | 1.0 | 0.8 | −0.2 | −0.3 | 30 |
| Opsanus beta4,† | 0.7 | 0.3 | −0.4 | −0.5 | 71 |
| Platichthys flesus5,† | 0.6 | −0.4 | −1.0 | −0.3 | 50 |
| Anguilla anguilla6,‡ | 3.0 | 0.9 | −2.1 | - | (70) |
| Pseudopleuronectes americanus7,‡ | 3.1 | 1.2 | −1.9 | - | (61) |
| Pseudopleuronectes americanus8,‡ | 5.5 | 2.0 | −2.5 | - | (45) |
| Platichthys flesus9,‡ | 6.5 | 2.2 | −4.3 | - | (66) |
| Platichthys flesus10(FW)‡ | 15.8 | 9.1 | −6.7 | - | (42) |
| Platichthys flesus10(SW)‡ | 26.6 | 18.5 | −8.1 | - | (30) |
| Platichthys flesus11(FW)‡ | 1.7 | 1.1 | −0.6 | - | (35) |
| Platichthys flesus11(SW)‡ | 2.5 | 1.7 | −0.8 | - | (32) |
| Platichthys lethostigma12 | 2.1 | 1.9 | −0.2 | - | (10) |
| Gillichthys mirabilis13,‡ | 2.5 | 1.3 | −1.2 | - | (48) |
| Species . | Net Cl− flux . | Net Na+ flux . | ΔNa+-Cl− . | Net HCO3− flux . | % of Cl− flux . |
|---|---|---|---|---|---|
| Parophrys vetulus1,§ | 0.4 | 0.2 | −0.2 | −0.2 | 50 |
| Citharichthys dordidus2,* | 3.5 | 2.3 | −0.9 | −0.9 | 26 |
| Platichthys flesus3,* | 1.0 | 0.8 | −0.2 | −0.3 | 30 |
| Opsanus beta4,† | 0.7 | 0.3 | −0.4 | −0.5 | 71 |
| Platichthys flesus5,† | 0.6 | −0.4 | −1.0 | −0.3 | 50 |
| Anguilla anguilla6,‡ | 3.0 | 0.9 | −2.1 | - | (70) |
| Pseudopleuronectes americanus7,‡ | 3.1 | 1.2 | −1.9 | - | (61) |
| Pseudopleuronectes americanus8,‡ | 5.5 | 2.0 | −2.5 | - | (45) |
| Platichthys flesus9,‡ | 6.5 | 2.2 | −4.3 | - | (66) |
| Platichthys flesus10(FW)‡ | 15.8 | 9.1 | −6.7 | - | (42) |
| Platichthys flesus10(SW)‡ | 26.6 | 18.5 | −8.1 | - | (30) |
| Platichthys flesus11(FW)‡ | 1.7 | 1.1 | −0.6 | - | (35) |
| Platichthys flesus11(SW)‡ | 2.5 | 1.7 | −0.8 | - | (32) |
| Platichthys lethostigma12 | 2.1 | 1.9 | −0.2 | - | (10) |
| Gillichthys mirabilis13,‡ | 2.5 | 1.3 | −1.2 | - | (48) |
Flux values are in mequiv kg−1 h−1 orμequiv cm−2 h−1.
FW, freshwater; SW, seawater.
ΔNa+-Cl− transport shows the difference between Na+ and Cl− net absorption. For four of the eight species represented, net HCO3− secretion(negative net flux) was also determined. For these four species, the magnitude of net HCO3− secretion is similar to theΔNa+-Cl− transport, suggesting that Cl− uptake, in excess of Na+ uptake, is driven by HCO3−/Cl− exchange. The column labeled `% of Cl− flux' shows the fraction of Cl− uptake that may be accounted for by anion exchange based on simultaneous measurements of HCO3− secretion. Values in parentheses are calculated assuming thatΔNa+-Cl− can be accounted fully for by anion exchange.
1 (Grosell et al., 1999); 2(Grosell et al., 2001); 3(Grosell and Jensen, 1999); 4(M.G., unpublished); 5 (Grosell et al.,2005); 6 (Marvao et al.,1994); 7 (Field et al.,1980); 8 (Musch et al.,1990); 9 (Mackay and Lahlou,1980); 10 (Smith et al.,1975); 11 (Gibson et al.,1987); 12 (Hickman,1968); 13 (Loretz,1996).
Transport by isolated epithelia under asymmetrical conditions in absence of an osmotic gradient.
Transport by isolated epithelia under asymmetrical conditions with osmotic pressure in serosal fluids>mucosal fluids.
Transport by isolated epithelia under symmetrical conditions.
In situ perfusion.