STIMULATION OF GOBLET CELL MUCOUS SECRETION BY ACTIVATION OF NERVES IN RAT CONJUNCTIVA

An epithelial debridement wound, as a stimulus to the cornea, causes c onjunctival goblet cell mucous secretion in that eye. To determine if this stimulation of secretion is neurally mediated, rats were anesthet ized and the local anesthetic lidocaine (1%) or buffer alone was admin istered topically and/or subconjunctivally for 15 min. A corneal epith elial debridement wound was made in one eye. The contralateral eye ser ved as the control. After 5-120 min, animals were sacrificed and infer ior bulbar conjunctival buttons removed. Mucus in the goblet cells was stained with Alcian blue and periodic acid-Schiff's reagent to indica te mucin-containing goblet cells. The number of mucin-containing goble t cells/0.16 mm(2) was determined by light microscopy; a decrease in n umber indicated an increase in mucous secretion. Stimulation by cornea l wounding induced goblet cell mucous secretion in that eye. Secretion was observed as rapidly as 5 min after stimulus and for as long as 12 0 min. Topical application of lidocaine, subconjunctival injection of lidocaine, or a combination of both inhibited wound-induced stimulatio n of mucous secretion. We conclude that conjunctival goblet cell mucou s secretion can be neurally mediated and could serve as an immediate r esponse to protect the ocular surface.