Prostaglandin agonists in glaucoma
pressure by increasing the uveoscleral outflow of aqueous humour. According to the hypothesized mechanism of action, these drugs bind to the prostaglandin F receptors in the ciliary muscle and initiate a signalling cascade in the cell nucleus that induces the production of matrix metalloproteinases. These enzymes initiate degradation of extracellular matrix components such as collagens in the ciliary muscle to increase spaces among ciliary muscle fibers, thereby reducing hydraulic resistance in the uveoscleral outflow pathway. Since prostaglandin agonists are inflammatory mediators, the most important side effects are hyperaemia and irritation of the eye. They also cause iris pigmentation. For an overview of prostaglandin synthesis click here.