The research project proposed in this grant involves characterizing the subtypes of the nicotinic receptor in the retina. The neurotransmitter acteylcholine and the nicotinic receptor play a vital role in cell signaling in the retina. The development of the visual pathway and possibly actual ocular growth both depend on specific subtypes of nicotinic receptors. The aims of my research include: (1) Characterization of the dominant subtypes of the nicotinic receptor in the retina using subtype specific drugs in pharmacological binding assays and subunit specific antibodies in immunoprecipitation experiments and western blotting. (2) Examination of the regulation of the nicotinic receptor by nicotine and NGF in vivo and in cultures of retinal explants. (3) Determination of which subtypes of the nicotinic receptor are transported down the optic nerve to the lateral geniculate nucleus and the superior colliculus.