Characterization of Prostaglandin F2α Receptors in Human Eyelids

This study aimed to identify and characterize the location of prostaglandin F_2α (PGF_2α) receptors in human hair follicles, particularly in the context of eyelash changes observed with glaucoma treatment. Using immunohistochemistry on eyelid specimens from 15 patients (10 men, 5 women, mean age 77 ± 14 years), the researchers found that PGF_2α receptors were present exclusively in the anagen phase hair follicles. The receptors were predominantly located in the inner root sheath of the bulb and stem, with the strongest staining in the matricular cells and inner sheath layer of the bulb, and the Huxley layer of the inner sheath in the stem. This suggests that the elongation, thickening, and crowding of eyelashes seen with prostaglandin analog use may be due to the presence of these receptors in specific parts of the hair follicle.