An adrenergic mechanism for visual neuroregulation

Studies of the diffuse electroretinogram (ERG) and evoked reponses in the optic lobe in the baby chick have shown that epinephrine produces changes in both. Epinephrine produces enhancement of the a-wave and depression of the b- and d-waves in both intact and isolated eyes. In the optic lobe it produces enhancement of both components of the evoked response. The presence of epinephrine in the vertebrate retina and the optic lobe of chicks suggests that these changes may reflect the involvement of epinephrine in synaptic transmission.