Influence of Temperature, Environmental Salinity and Fasting on the Patterns of Fatty Acid Synthesized by Gills and Liver of the European Eel (Anguilla Anguilla)

A rise in temperature on the average from 8 to 28 degrees C resulted in an enhanced relative incorporation of 1-14Cacetate into saturated fatty acids in liver tissue. The same effect was seen in gill tissue, but only after incubation in vitro and when the precursor was injected into the eel. When 1-14Cacetate was added to the water in the incubation tank such a "homeoviscous adaption" was not observed in gill tissue. A rise in temperature resulted in less relative incorporation of radioactivity into saturated gill fatty acids. We attribute this difference to a specific labelling of salt transport cells in the gills, due to the labelled precursor itself taking part in biological ion transport when it is added to the water. It would appear that palmitoleic acid plays a special role in the function of the salt transport cell. When 1-14Cacetate was added to the water in the incubation tank there was a significantly enhanced percentage incorporation into saturated gill fatty acids in fresh water relative to sea water. Fasting led to less relative incorporation of 1-14Cacetate into saturated liver fatty acids in vitro.