Figure 7:
a) Wiring diagram of the possible input and output neurons that the dopamine amacrine cell (Toh-IR, A28) is most likely involved with in the IPL of the turtle retina.

The tristratified Toh-IR cell (red) is probably driven primarily by B4 and B9 bipolar cells and amacrine cells A12 and A15 because of complete costratification of their processes although all other amacrine and bipolar types could also be involved in a more minor role. The Toh-IR cell most likely synapses upon ganglion cells G11, G18, G19 and G20 for reasons described in the text. The five strata of the IPL are indicated and the center response sign of the various candidate cells are also indicated as black for OFF-center, gray for ON-center and black/gray for ON-OFF cells.

b) Putative synaptic pathway, neurotransmitter systems (DOPA, Glut, serotonin, GABA) and receptor types (GABAc, GABAc D1 and D2) that could be influencing the response characteristics of the dopamine amacrine (DOPA, red cell).

See text for a more detailed explanation.