EDN1 and glaucoma: In this issue L. Choritz et al. investigate whether increased concentrations of endothelin-1 in the aqueous humor samples of glaucoma patients influenced wound healing and bleb fibrosis after standard trabeculectomy with mitomycin C. Endothelin-1 is a potent vasoconstrictor produced in the eye by the ciliary epithelium and to be released into the aqueous humor.