Table 2. Model parameter values (for one cell) obtained from direct measurements on granulosa cells in vitro or from the published literature values.
| Parameter (units) | Symbol | Value |
| mRNA degradation (/min) | δmRNA | 6.00×10−3a |
| protein degradation (/min) | δprot | 3.00×10−3a |
| Aromatase mRNA synthesis (pg/min) | υmRNA.Cyp19 | 3.00×10−10b |
| Hsd17b1 mRNA synthesis (pg/min) | υmRNA.Hsd 17b1 | 6.00×10−10b |
| Hsd17b2 mRNA synthesis (pg/min) | υmRNA.Hsd 17b2 | 4.20×10−11b |
| Aromatase protein synthesis (/min) | υprot.Cyp 19 | 6000b |
| Hsd17b1 protein synthesis (/min) | υprot.Hsd 17b1 | 6300b |
| Hsd17b2 protein synthesis (/min) | υprot.Hsd 17b2 | 6000b |
| Maximal reaction rates Vmax (pmoles/min/pg enzyme) | ||
| Hsd17b2, T → A reaction | λHsd 17b2,T | 6.65×10−8c |
| Hsd17b2, E2 → E1 reaction | λHsd 17b2,E2 | 7.91×10−8c |
| Michaelis-Menten constants (pmoles) | ||
| Hsd17b2, for T | ξHsd 17b2,T | 5.67×10−6c |
| Hsd17b2, for E2 | ξHsd 17b2,E2 | 5.40×10−6c |
| A extra- over intra-cellular partition coefficient (unitless) | Roi,A | 0,0124d |
| T extra- over intra-cellular partition coefficient (unitless) | Roi,T | 0,013d |
| E1 extra- over intra-cellular partition coefficient (unitless) | Roi,E 1 | 0,0084d |
| E2 extra- over intra-cellular partition coefficient (unitless) | Roi,E 2 | 0,0108d |
| A excretion rate constant (ml/min) | Kout,A | 1×10−8e |
| T excretion rate constant (ml/min) | Kout,T | 1×10−8e |
| E1 excretion rate constant (ml/min) | Kout,E 1 | 1×10−8e |
| E2 excretion rate constant (ml/min) | Kout,E 2 | 1×10−8e |
| Ovary blood flow (ml/min) | Fov | 0.2654f |
| Individual granulosa cell volume (ml) | VGC | 0.27×10−9 mlg |
A, androstenedione; T, testosterone; E1, estrone; E2, estradiol.
b
mRNA and protein synthesis rates were calculated under steady-state assumption with data from direct measurements on granulosa cells in vitro (see text).
c
Renwick et al., 1981 [49].
d
Breen et al., 2009 [26].
e
Data were arbitrately fixed.
f
Plowchalk and Teeguarden, 2002 [50].
g
Direct in vitro measurement.