Animal model for cystic fibrosis: pulmonary clearance of Staphylococcus aureus in mice treated with reserpine.

Since it has been demonstrated that chronic administration of reserpine to rats produces CF-like alterations, we have studied the lung resistance to bacterial infections in animals treated with reserpine. Mice of the BALB/c inbred strain were injected subcutaneously with different doses of reserpine for 7 days; after, they were submitted to an infective aerosol containing $\text{Staphylococcus aureus}$ in a nebulization chamber. With each pair of exposed animals, an individual value of the uncleared bacteria ratio (UBR) at 4 hours was obtained. Reserpinized animals showed a significant increase in UBR values when compared to control mice (p < 0.05 and p < 0.01 depending on the doses), suggesting an impairment of the lung antibacterial defenses. Although pharmacological doses of reserpine produce catecholamine depletion, we can not conclude that this action upon the nervous system is the only cause of the CF-like response we detected. In conclusion, the observed UBR decrease lends support to the concept of a reserpine-induced CF animal model.