This grant proposes to study the physiological and pharmacological properties of goldfish bipolar cells. Single cells, dissociated from goldfish retina and maintained in tissue culture, will be studied using newly-developed patch-clamp recording methods. These methods make possible the study of single channels in cell membranes. They also provide a means for recording from and voltage clamping small cells. They can provide information about the physiology of nerve membranes in much greater abundance and detail than was previously possible. We shall use these techniques to study bipolar cells, since these retinal neurons are of essential importance in the processing of visual signals, and since little is known about their function. The purpose of our experiments is to provide fundamental knowledge about the basic menbrane properties of bipolar cells: their membrane resistance and capacitance, the nature of their resting potentials, and the function of voltage-dependent and other conductances present in the bipolar cells. We shall also investigate the effects of pharmacological agents, and in particular of putative neurotransmitter substances on isolated bipolar cells. In this way we can investigate the effects of these drugs on the bipolar cells themselves, free of the complications produced by their connections to other cell types. In addition to providing basic information about the physiology of vertebrate retina, we hope also to provide useful knowledge about the pharmacology of retinal cells, which may assist in the assessment of the effects of pharmacological agents on acuity and other measures of visual function.
