Intrapleural administration of gelatin-embedded, sustained-release basic fibroblast growth factor for the regeneration of emphysematous lungs in rats

Background: Intra-airway and intra-arterial administration of gelatin-embedded, sustained-release basic fibroblast growth factor has stimulated regeneration of emphysematous lungs in animal experiments, but these routes of administration may also cause harm. This study investigated the effectiveness of intrapleural administration of gelatin-embedded, sustained-release basic fibroblast growth factor. This animal experiment preceded our clinical trial of intrapleural administration of sustained-release basic fibroblast growth factor in patients with chronic obstructive pulmonary disease accompanied by pneumothorax. Methods: Pulmonary emphysema was induced in Sprague-Dawley rats using porcine elastase. Gelatinembedded, sustained-release basic fibroblast growth factor was administered via the left pleural cavity. The rats were divided into a group that received gelatin-embedded, sustained-release basic fibroblast growth factor (FGF-group, n = 6), and a group that did not (FGF-group, n = 6). Animals were sacrificed after 14 days, and the results were evaluated by histologic examination. Results: In the FGF-group, the mean linear intercept value of the alveolar septa was significantly shorter on the treated side than on the untreated side (65.1 +/- 7.0 vs 114.4 +/- 7.5 mu m; P=.0005). There was no significant difference in the mean linear intercept value between the treated and untreated sides in the FGF-group. Conclusions: Intrapleural administration of sustained-release basic fibroblast growth factor induced lung regeneration in rats with elastase-induced pulmonary emphysema.