Table 2.

Parameters and properties used in MCell simulations

Parameter	Value	Unit
DA diffusion coefficient a	4.00 × 10−6	cm2/s
Vesicle release probability b	0.06
Average firing rate of DA neurons c	4.00	Hz
DA released per release event d	3250	n
OF → OF* rate constant (k12) e	9.60 × 106	M−1s−1
OF* → IF* rate constant (k23) e	20.00	s−1
IF* → IF rate constant (k34) e	5.00	s−1
IF ↔ OF forward rate constant (k41) e	2.00	s−1
IF ↔ OF reverse rate constant (k14) e	8.00	s−1
Total axonal surface area f	337.16	μm2
Uniform DAT surface density, ρ(DAT) f, g	800	1/µm2
High DAT surface density, ρh(DAT) f, h	6,339	1/µm2
Low DAT surface density, ρl(DAT) i	50	1/µm2
Very high DAT surface density, ρh2(DAT) j	30,000	1/µm2
DA density of neurons, IDA	9.3	μg/cm3
Ratio of the total DA released per AP, R	0.05%
Density of DA terminals, ρterm	0.104	1/μm3

^aFrom Rooney and Wallace (2015).

^bReported in Dreyer et al. (2010)

^cSee Dreyer et al. (2010).

^dSee Pothos et al. (1998).

^eEstimated from molecular computations.

^fDerived from Block et al. (2015).

^gCase 1 in Fig. 2.

^hHigh-density region in case 21; see Fig. 2.

ⁱLow-density region in cases 2–4.

^jVery-high-density region in cases 3 and 4.