Human conjunctival mucosa

Figure 3. Human conjunctival mucosa following reaction with FITC labeled lectins. Controls. Pretreatment with neuraminidases of sections (3a Vibrio cholerae prior to LFA incubation, 3c Newcastle disease virus prior to MAA incubation) and preincubation of lectins with Fetuin (3b with LFA, 3d with MAA) reduced or abolished the labeling results. Bar equals 50/xm. 

In an investigation of the ability of different molecular substances to elicit ocular anaphylaxis when applied topically to the eye, Kahn et al. (1990) concluded that only substances having a molecular weight less than 3500 penetrate the conjunctival barrier. Therefore, systemic delivery via the ocular route seems to rely on overflow of the instilled dmg to the nasal cavity. Thus, the nasal mucosa contributed about 4 times more than the conjunctival mucosa to the systemic absorption of ocularly applied insulin (Yamamoto et al, 1989). Topically applied insulin administered chronically without surfactant seems to be nontoxic to the external human eye (Bartlett etal, 1994a). 

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