Fig. 6.

The performance of the model is examined by changing the parameter values in several ways. Once again, the solid, dashed, and dotted lines represent the voltages over time at the soma, right tip and left tip, respectively. (a) The full model used the parameter values in Table 1. (b) The delay in GABA channel closing time is reduced, by multiplying α, β by 3 and doubling θ ₂ (i.e., the postsynaptic Cl⁻ conductance closely reflects the presynaptic voltage). The Cl⁻ gradient along the SAC dendrites is as in case (a)) and Table 1. The DS effect is preserved almost intact in this case. (c, d) the GABA (Cl⁻) reversal potential gradient from Fig. 2(b) is eliminated, and it is replaced by a constant reversal potential of −55 mV, corresponding to the absence of active the Cl⁻ cotransporters (c) or −80 mV, corresponding to the presence of the K⁺-Cl⁻ cotransporter located along the entire length of the dendrites (d). A DS effect is preserved in the inhibitory case (d), but not in the shunting case (c). In cases (c) and (d), the delay in GABA channel closing is as in case (a) and Table 1