Possible Mechanism of Action of the Antiallergic Effect of an Aqueous Extract of Heliotropium indicum L. in Ovalbumin-Induced Allergic Conjunctivitis

Figure 5

Photomicrographs of the conjunctival tissues in OIAC in guinea pigs treated with 30, 100, and 300 mg kg⁻¹ HIE, 30 mg kg⁻¹ prednisolone, 10 mg kg⁻¹ chlorpheniramine, and PBS, compared to that of normal guinea pigs.

(a) Normal conjunctival tissue with normal epithelial architecture without evidence of mononuclear infiltration

(b) 30 mg kg⁻¹ prednisolone treated with mild mononuclear infiltration into the subepithelial tissue of the conjunctiva

(c) PBS-treated conjunctival tissue with widespread infiltration of neutrophils and eosinophils

(d) 10 mg kg⁻¹ chlorpheniramine treatment with remarkably unresolved inflammatory process seen as intense polymorphonuclear infiltration

(e) 30 mg kg⁻¹ HIE treated with mild infiltration of neutophilic and eosinophilic cells

(f) 100 mg kg⁻¹ HIE treated conjunctival tissue with moderately diffuse neutrophils and eosinophils exudation

(g) 300 mg kg⁻¹ HIE treated with mild neutophils and eosinophil infiltration in subepithelial conjunctival tissue