ISOLATION AND CHARACTERIZATION OF RAT PRIMARY LUNG-CELLS

Lung cell culture may be useful as an in, vitro alternative to study t he susceptibility of the lung to various toxic agents. Lungs from fema le Wistar rats were enzymatically digested by recirculating perfusion through the pulmonary artery with a sequence of solutions containing d eoxyribonuclease, chymopapain, pronase, collagenase, and elastase. Lun g tissue was microdissected and resuspended and the cells obtained wer e washed by centrifugation. By this isolation method, 2 x 10(8) cells per rat lung were obtained with an average viability of 97%. Lung cell s cultured in medium containing antibiotics and serum maintained a via bility of > 70% for 5 d. Rat primary lung cells were exposed to variou s toxic agents and their viability was assessed by formazan production capacity after 18 h of incubation. Compared to rat and mouse hepatocy te cultures (EC(50) = 5.8 mM), rat primary lung cells were much more s usceptible to hydrogen peroxide (EC(50) = 0.6 mM). All cell types were equally sensitive to the more potent toxicant tert-butylhydroperoxide (EC(50) = 0.1 mM). Paraquat was more toxic to lung cells (EC(50) = 0. 03 mM) than to rat (EC(50) = 2.8 mM) and mouse (EC(50) = 0.2 mM) hepat ocytes. In contrast, rat lung cells were less sensitive to sodium nitr oprusside (EC(50) = 2.6 mM) compared to rat (EC(50) = 0.2 mM) and mous e (EC(50) = 0.03 mM) hepatocytes. Nitrofurantoin and menadione (at EC( 50) = 0.04 mM and 0.006 mM, respectively) were more toxic to rat lung and liver cells than to murine hepatocytes (EC(50) = 0.2 mM and 0.04 m M, respectively). Our findings demonstrate the applicability of this r at primary lung cell culture for studying the effects of lung toxicant s.