ISSN:
1432-2013
Schlagwort(e):
Sodium and Chloride Transport
;
Intestinal Mucosa Permeability
;
Fish Osmoregulation
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Medizin
Notizen:
Summary 1. Everted intestinal sacs prepared fromPlatichthys flesus adapted to sea water (SW) have higher rates of salt and water transport than did sacs prepared from fresh water adapted (FW) fish. 2. Intestines mounted in Ussing chambers gave stable open-circuit voltages and short-circuit currents after pre-incubation for 20–30 min of −1.91±0.14 (14) mV and −45.0±5.1 (14) μA/cm2, SW fish, and −1.24±0.14 (11) mV and −18.2±3.6 (11) μA/cm2, FW fish. 3. Isotope flux measurements indicated a net Na transport of 21.5±4.1 (11) neq/cm2·min in SW fish intestines, but no significant Na transport in FW fish (7.6±7.6 (9) neq/cm2·min). Both preparations showed an active Cl transport, 26.6±6.1 (12) neq/cm2·min for SW and 18.5±9.7 (17) neq/cm2·min for FW fish. 4. No significant difference in the uptake of Na or Cl across the mucosa was observed between FW and SW fish. The uptake of both ions showed some saturation at high concentrations. 5. Interactions between Na and Cl uptake were small, although Cl uptake was significantlyhigher in Na-free solutions. 6. It is concluded that electrogenic Cl transport may be the dominant mechanism for water and salt transport in flounder intestine, and that adaptation to a saline environment involves regulation of pumping rather than of Na or Cl entry across the mucosal membrane.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF00585984
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