Alveolar and saccular lung phospholipids of the anaconda, Eunectes murinus

Abstract

Phospholipids and their mode of synthesis in lung samples from the alveolar and saccular regions of an anaconda (Eunectes murinus) were investigated by standard techniques of chloroform–methanol extraction and two-dimensional thin-layer chromatography. The alveolar lung has six times as much phosphatidylcholine in its lung wash lipid extract as saccular lung. Phosphatidylcholine and sphingomyelin are the two principal phospholipids of the tissue of both lungs. Alveolar lung incorporates a higher percentage although a smaller total amount of [1-14C]acetate (54%) into phosphatidylcholine (including lysophosphatidylcholine), whereas saccular lung only incorporates 8% [1-14C]acetate into phosphatidylcholine (including lysophosphatidylcholine) and 60% [1-14C]acetate into sphingomyelin. Saccular lung synthesized 31% disphosphatidylglycerol from [1-14C]acetate; alveolar lung did not synthesize any. Surface tension plots of lung wash lipid extracts show slight surpellic activity with minimum surface tensions of 22 dyn/cm (1 dyn = 10 μN) for both alveolar and saccular lung, at 37 °C.