Figure 2.

The relative cholinergic expression (number of ChAT-containing neurons) in homologous and heterologous cultures as a function of the number of neurons in the cultures. The open circles show the cholinergic function as the ratio of normal neurons on trisomic glia to trisomic neurons on normal glia. The circles with crosses show that ratio of expression for trisomic neurons on trisomic glia to that for normal neurons on normal glia. Note that at low neuronal density, the heterologous cultures containing Ts16 glia have relatively low numbers of cholinergic neurons, whereas at high neuronal density the heterologous cultures having Ts16 neurons have the lower number of cholinergic neurons.