Surfactant deficiency with decreased opsonic activity in a guinea pig model of alcoholism

Chronic alcoholism was induced in guinea pigs to quantitate the effect of alcohol on lung surfactant. Animals were studied after 6 weeks of treatment with either ethanol (ETH) or isocaloric dextrose saline (DEX) injections. The amount of surfactant retrieved by bronchoalveolar lavage (BAL) was evaluated by measuring the quantity of phosphatidylcholine (PC) and disaturated phosphatidylcholine (DSPC) in the fluid. The amount of DSPC recovered from the ETH animals (40.9 +/- 10.4 micrograms/ml of BAL fluid, mean +/- SD) was significantly lower than from the DEX animals (82.7 +/- 18.6 micrograms/ml of BAL fluid, p less than 0.001). This decrease in surfactant was associated with impairment of the opsonic activity from BAL fluid in the ETH versus DEX animals using a standard assay of bacterial (Staphylococcus aureus) killing with normal polymorphonuclear leukocytes and BAL fluid as an opsonin. We conclude that in the guinea pig model of alcoholism, surfactant deficiency occurs and has physiologic importance in reduced bacterial killing.