Alveolar type II (ATII) cells perform many important functions within the lung, including surfactant metabolism. We have investigated the effects of isoflurane and different i.v. anaesthetics on cell metabolism in primary cultures of rat ATII cells. Biosynthesis of phosphatidylcholine, the main phospholipid component of surfactant, was decreased in cells exposed to isoflurane in a dose- and time-related manner. This effect was fully reversible within 2 h after isoflurane removal. Lactate dehydrogenase (LDH) release, an index of cell damage, was increased with isoflurane exposure (1%) over a long incubation period (8-12 h). Enhanced lactate production, reflecting an increase in glycolytic metabolism, was also observed in isoflurane exposed cells. In contrast, metabolism of ATII cells was moderately affected by i.v. anaesthetics. Our data suggest differential metabolism of alveolar homeostasis depending on the anaesthetic agent used.