Comparison of membrane phospholipids of the rabbit and pig crystalline lens

Crystalline lenses excised from 5-7-month-old rabbits and pigs were extracted for lipids with chloroform/methanol, 2/1 using the Folch method. The extracted crude lipids were analyzed at 202 MHz by 31P-NMR spectroscopy. Twelve membrane phospholipids were detected. Both rabbit and pig phospholipid profiles contained phosphatidylcholine (PC), lysophosphatidylcholine, phosphatidylcholine plasmalogen, phosphatidylethanolamine (PE), phosphatidylethanolamine plasmalogen (PE plas), phosphatidylserine, sphingomyelin (SPH), and an uncharacterized phospholipid. In addition, pig lens profiles contained lysophosphatidylethanolamine, phosphatidylinositol, cardiolipin and phosphatidylglycerol. The data indicate that these two animal models have significant differences in membrane phospholipid profiles. In each species, however, the bulk phospholipid component resides in the neutral phospholipids PC, PE, PE plas, and SPH.