PRESSURE ACCLIMATION OF THE EEL AND LIVER MEMBRANE-COMPOSITION

Homeoviscous adaptation of membrane fluidity is known to exist in fish living at great depths. Is this adaptation also present in fish livin g near the surface but experimentally acclimated to high pressure? The composition of mitochondria-rich fractions extracted from the livers of eels acclimated for 15 days at 101 ATA was determined. The results show that pressure induced a significant increase (+100%) of total pho spholipids (PL) and cholesterol without a change in their ratio. The i ncrease of PL content was accompanied by a decrease in phosphatidylcho line in favour of phosphatidyl ethanolamine which, due to its preferen ce for the H-II form, is able to compensate for the loss in fluidity i nduced by pressure.