Figure 5
(a) Schirmer tear secretion test results: Graphs indicate variations in tear secretion induced by 5, 50 and 100 µg/ml of capsaicin exposure in rats. Each column and vertical bar shows the mean ± standard deviation (n = 6). An asterisk indicates statistically significant differences (***P < 0.001, *P < 0.05). Statistically significant differences were observed in capsaicin treated groups when compared with the control groups. Transcorneal permeation profile of 50 mg/ml capsaicin versus 50 mg/ml of dexamethasone (standard): (b) Capsaicin and dexamethasone showed similar and rapid permeation across the corneal membranes initially until the 1st hour, which was followed by a linear and gradual decrease later. The permeability rate exhibited rapid and fast absortion of about 53.8% capsaicin (26.9 mg/cm2) as compared to 45.8% (22.9 mg/cm2) dexamethasone in the first hour. Earlier studies suggest considerable permeation and absorption of dexamethasone when formulated in cyclodextrine microparticle carrier systems via the ocular topical route31. Values are mean ± standard deviation (n = 4). Statistically significant differences were observed in capsaicin treated groups when compared with the control group (***P < 0.001, *P < 0.05).
