607628
constant: true
value: 0.01
name: ky
type: Parameter

607633
constant: true
value: 1.0
name: C2
type: Parameter

607602
constant: true
units: litre
size: 1.0
spatial dimensions: 3.0
type: Compartment

570449
unit: 570461
name: first_order_rate_constant
type: SBMLUnitsDef

570485
exponent: 1.0
scale: 0
multipler: 3600.0
kind: SECOND
type: SBMLUnit

607622
constant: true
value: 1.3
name: k2
type: Parameter

570437
exponent: 1.0
scale: 0
multipler: 3600.0
kind: SECOND
type: SBMLUnit

607618
constant: false
value: 1.9
name: IL6
type: Parameter

607624
constant: true
value: 0.9
name: k4
type: Parameter

607614
constant: false
value: 500.0
name: X
type: Parameter

MODEL1006230083
modified:
  W3 CDTF: Fri Jun 25 14:40:08 BST 2010
name: Kroll2000_PTH_BoneFormationDesorption
parameter: 607628
length unit: 493212
parameter: 607617
rule: 607607
curated: false
creator:
  ORG:
    orgname: University of Auckland
  n:
    given: Catherine
    family: Lloyd
parameter: 607627
units def: 570425
parameter: 607632
type: SBMLModel
is described by: http://identifiers.org/pubmed/10824426
modified:
  W3 CDTF: Fri Jun 25 14:40:08 BST 2010
parameter: 607613
parameter: 607622
compartment: 607602
created:
  W3 CDTF: Fri Jun 25 14:40:08 BST 2010
modified:
  W3 CDTF: Fri Jun 25 14:40:08 BST 2010
parameter: 607619
parameter: 607618
rule: 607606
volume units: 290956
rule: 607611
substance units: 178797
units def: 570449
rule: 607609
parameter: 607633
units def: 570473
parameter: 607615
parameter: 607614
parameter: 607624
parameter: 607623
parameter: 607620
parameter: 607629
area units: 237671
parameter: 607630
rule: 607610
creator:
  ORG:
    orgname: University of Auckland
  n:
    given: Catherine
    family: Lloyd
parameter: 607634
notes: This a model from the article: Parathyroid hormone temporal effects on bone formation and resorption. Kroll MH. Bull Math Biol 2000 Jan;62(1):163-88 10824426 , Abstract: Parathyroid hormone (PTH) paradoxically causes net bone loss (resorption) when administered in a continuous fashion, and net bone formation (deposition) when administered intermittently. Currently no pharmacological formulations are available to promote bone formation, as needed for the treatment of osteoporosis. The paradoxical behavior of PTH confuses endocrinologists, thus, a model bone resorption or deposition dependent on the timing of PTH administration would de-mystify this behavior and provide the basis for logical drug formulation. We developed a mathematical model that accounts for net bone loss with continuous PTH administration and net bone formation with intermittent PTH administration, based on the differential effects of PTH on the osteoblastic and osteoclastic populations of cells. Bone, being a major reservoir of body calcium, is under the hormonal control of PTH. The overall effect of PTH is to raise plasma levels of calcium, partly through bone resorption. Osteoclasts resorb bone and liberate calcium, but they lack receptors for PTH. The preosteoblastic precursors and preosteoblasts possess receptors for PTH, upon which the hormone induces differentiation from the precursor to preosteoblast and from the preosteoblast to the osteoblast. The osteoblasts generate IL-6; IL-6 stimulates preosteoclasts to differentiate into osteoclasts. We developed a mathematical model for the differentiation of osteoblastic and osteoclastic populations in bone, using a delay time of 1 hour for differentiation of preosteoblastic precursors into preosteoblasts and 2 hours for the differentiation of preosteoblasts into osteoblasts. The ratio of the number of osteoblasts to osteoclasts indicates the net effect of PTH on bone resorption and deposition; the timing of events producing the maximum ratio would…
creator:
  ORG:
    orgname: University of Auckland
  n:
    given: Catherine
    family: Lloyd
time units: 570473
parameter: 607625

570425
unit: 570437
name: hour
type: SBMLUnitsDef

570473
unit: 570485
name: time
type: SBMLUnitsDef

607620
constant: true
value: 1.0
name: k1
type: Parameter

607630
constant: true
value: 2.0
name: K2
type: Parameter

570461
exponent: -1.0
scale: 0
multipler: 3600.0
kind: SECOND
type: SBMLUnit

607634
constant: true
value: 1.0
name: C3
type: Parameter

607632
constant: true
value: 1.0
name: C1
type: Parameter

607615
constant: false
value: 10.0
name: P
type: Parameter

607617
constant: false
value: 200.0
name: Z
type: Parameter

607613
constant: false
value: 10.0
name: Y
type: Parameter

607619
constant: true
value: 50.0
name: C
type: Parameter

607623
constant: true
value: 0.05
name: k3
type: Parameter

607629
constant: true
value: 5.0
name: K
type: Parameter

607627
constant: true
value: 0.02
name: k6
type: Parameter

607625
constant: true
value: 5.0
name: k5
type: Parameter