Mass cells in ocular tissues of normal rats and rats infected with Nippostrongylus brasiliensis.

In orbital exenteration specimens from 14 rats, 93% of the mast cells were found in the lids, the limbus, and the conjunctiva, 5% in the orbital tissues, and less than 1% in the globe. The density of mast cells was highest in lid (2843/mm3), limbus (2822/mm3), and orbit (2184/mm3) and lowest in bulbar conjunctiva (794/mm3), ciliary body (512/mm3), and sclera (176/mm3). There was no significant difference in the distribution or density of mast cells in orbital exenteration specimens from normal rats compared with rats infected with the worm Nippostrongylus brasiliensis. We concluded that certain ocular structures are rich in mast cells, which suggests that these structures might be susceptible to injury mediated by mast cell products.