Retinal cells which secrete acytyl choline

Important facts about signal transduction in Retina The responses of the rods, cones and horizontal cells are hyperpolarizing. Bipolar cells may show either hyperpolarization or depolarizationQ . All these cells develop only graded local potentials, i.e., nonpropagated, decremental, does not follow all or none law. These cells do not develop action potential. The only cell which develops propagated action potential is ganglion cellsQ and the response is always depolarizing. Otherwise, they remains in inactive state, Amacrine cells produce depolarizing potential and spikes, Rods and cones release glutamateQ at their synapses with the bipolar cells. Amacrine cells0 secrete at least eight types of transmitter substances, including GABA, glycine, dopamine, acetylcholineQ and indolamine, all of which normally function as inhibitory neurotransmitters, The transmitters of the bipolar cells0 and horizontal cells are unclear.