Cellular content of the normal rabbit pleural space.

The cellular content of the pleural space of five normal rabbits was studied by three cytopreparative techniques using different methods of collection (aspiration, irrigation) and fixation (95% ethyl alcohol, 50% alcohol: 1% polyethylene glycol). The method using aspiration, 95% ethyl alcohol fixation, and the Papanicolaou stain was simple and provided the best cytologic detail. With this method 70.1% of pleural fluid cells were monocytic, 7.5% were monocytic with morphologic features typical of macrophages, 10.5% were lymphocytes, 8.9% were mesothelial cells and 1.9% were polymorphonuclear leukocytes. Other methods were technically more difficult and provided less cytologic detail. The cellular content of the normal rabbit pleural space is described, providing baseline information for the study of experimental pleural disease.