The involvement of melanopsin in the regulation of melatonin was also determined by using a specific inhibitor AA92593 and by inhibiting melanopsin-induced phospholipase C activation. Under this situation neither AANAT nor melatonin levels changed under light conditions (n = 4, ***p < 0.001). The discovery of melanopsin in the lens opens the possibility of regulating melatonin synthesis with the corresponding implication as an antioxidant substance[1].