Sialomucin complex (rMuc4) expression during development of the rat cornea

Purpose. To determine changes in sialomucin complex (SMC, rat Muc4) express ion in rat ocular surface tissue during development from birth to adult. Methods. Immunoblot and immunocytochemical analyses were performed on isola ted corneal tissue and rat eyes, respectively, from animals at days 1, 9 an d 15 after birth. Adult animals were used for comparison. Results. SMC was detected by immunoblotting at all ages (day 1-adult) and i ncreased into adulthood. Immunocytochemical localization also showed steadi ly increasing amounts of SMC to adulthood. The SMC was located at the apica l surface of the corneal epithelium and in the superficial layers of the st ratified corneal epithelium. Conclusions. SMC at the corneal surfaces steadily increases during developm ent to adulthood, but does not exhibit a marked transition in expression at the time of eye-opening.