Immunohistochemical distribution of 11β-hydroxysteroid dehydrogenase in human eye

11β-hydroxysteroid dehydrogenase (11β-HSD) regulates local actions of corticosteroids at glucocorticoid and mineralocorticoid receptors. Corticosteroids are thought to play important roles in ocular function. However, mechanisms of intraocular corticosteroid action are still unclear. Therefore, in this study, we examined the immunohistochemical localization of 11β-HSD type 1 (11β-HSD1), 11β-HSD type 2 (11β-HSD2), mineralocorticoid receptor (MR) and glucocorticoid receptor (GR) in human ocular tissues from patients (6 months to 78 years of age; n=10) retrieved from surgical pathology files. Both 11β-HSD2 and MR immunoreactivity was detected only in non-pigmented epithelium of the ciliary body, but was undetectable in cornea, lens, iris, retina, choroid and sclera, in all the cases examined. GR was detected in all cell types in the human eye. 11β-HSD1 immunoreactivity was not detected in the human eye in this study. These results suggest that 11β-HSD2 play an important role in human ocular mineralocorticoid action, such as the production of aqueous humor, in the ciliary body. The widespread expression of GR suggests that glucocorticoids may play an important role in the function and homeostasis of the human eye.