Diurnal fluctuation of intraocular pressure (IOP) is an important issue in managing glaucoma, yet its bases are not well understood. Delineating the genetic controllers and physiological pathways may open the door to potential therapeutic targets.
Miller and associates1 have provided evidence for a GPR18 role in the diurnal regulation of IOP in mice and explored the related endocannabinoid pathways. Albeit early in the game, the article is a noteworthy step in unraveling the mysteries of diurnal IOP variation, a phenomenon of considerable clinical importance.